THE PARENTING INSTINCT AND CHILDCARE IN THE HOMO SAPIENS AS SEEN IN MOST COMMUNITIES
Dr Jideofo Kenechukwu Danmbaezue
Instinct, in zoology and psychology, is the innate programming characteristic of a particular animal species that organises complex patterns of behaviour, enabling members of a species to respond appropriately to a wide range of situations in the natural world. Such behaviours are usually involved patterns of responses to particular stimuli and are often permanent patterns of feeding, mating, parenting, and expression of aggression. In each species, these characteristic behaviour patterns are developed and refined by the forces of natural selection in the process of evolution.
Some scholars make careful distinctions between learned behaviours and instinctive behaviours. In recent years, however, researchers have generally agreed that such distinctions are not particularly useful and that learning and instinct interact to direct an animal’s behaviour in appropriate ways. Instinctive behaviours are inherited from parents and are vitally important in helping an animal adapt to and survive in any and every ecological environment it finds itself. Thus, an animal transferred from one zoo to another in a different climate learns to adjust like others that were there before its arrival and so still lives a normal life!
Instinctive behaviours can be extremely complex even in relatively simple animals, for example, the remarkable navigational and communication skills possessed by honey bees. A worker bee may fly a quarter of a mile or more from the hive in search of flowers that are a good source of food. The sun usually serves as an indicator of direction, but the bee can navigate accurately, even in a moderate breeze, when a cloud hides the sun.
When it finds a good source of food, the bee has the capacity to calculate a true course back to the hive, allowing for wind and for apparent movement of the sun. Upon returning to the hive, it communicates the location of the food through a “dance” that conveys information about distance and direction. Other bees use this information to go directly to the food. In this example, learning and genetically coded patterns of behaviour each play an important role. Instincts permit an animal to show highly adaptive and often very complex behaviours without the necessity of learning those responses through trial and error.
The role that instinct plays in human behaviour is not yet clear. Some researchers feel that human behaviours such as aggression and territoriality may have instinctive components. Others feel that such a conclusion is not warranted by the available data and that human behaviour is qualitatively different from that of other animals. There is some danger of over generalising to human behaviour from animal research; however, many of the same forces that direct the behaviour of other animals are likely to influence human behaviour.
The term instinct can also be applied to several constructs developed by Sigmund Freud and other personality theorists (see Psychoanalysis). Freud theorized that there are instincts for life and for death, and that the sexual drive is essentially instinctive. This specific application of the term instinct is unrelated to the way in which behavioural scientists use the term.
The Stock Market/Rob Lewine
A Couple without Children
Many couples remain childless by choice or due to biological problems. Often they do not want children to disrupt their lovemaking! They marry for companionship! Childless families make up an increasing number of households in developed countries like France and the United States.
Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003
PARENT AND CHILDCARE
Parent and Child is a branch of the law of domestic relations that determines the legal rights and obligations of fathers or mothers to their children and of children to their parents. The legal relationship is distinguished from the natural relationship; for example, two persons may have a legal relationship of parent and child although there is no natural relationship, as in the case of an adopted child.
In common law, in the
and the United Kingdom , parents were the legal as well as natural
guardians of their child. They had the right to name the child and were
entitled to custody. As custodians, they could reasonably chastise the child,
but for excessive punishment, the parents were criminally liable for assault,
or for homicide in case of death. The father was deemed entitled to custody of
the child in preference to the mother. A parent was not liable for a tort
(wrongful act) of the child unless its commission was incited or authorized by
the parent. A parent could recover damages for torts committed against the
child. In common law, the parent was not civilly liable to maintain the child, but
was criminally responsible in cases of neglect, as when failure to provide food
or clothing caused injury or death. United States
The legal relationships of parent and child established under common law have been modified by statute in Britain and the U.S. In general, such statutes provide that a married woman is a joint guardian of her children with her husband, with equal powers, rights, and duties. Either parent has the right to custody of the children of the marriage, and in a divorce or separation, the court can award custody to the parent best qualified and able to care for the children. Parents must provide for their children such necessities of life as food, clothing, shelter, education, and medical care; if they cannot or will not, state laws authorize intervention by designated authorities to ensure that children's needs are met.
Children who are physically or emotionally abused by their parents may be the subjects of legal action in order to protect the children. Parents' rights to custody of their children may be limited or, in extreme cases, terminated because of failure to provide adequate care. Laws require a father to support his minor children if he is able to do so, whether or not he has ever been married to their mother. Failure to provide support may result in civil or criminal proceedings against him. If paternity has been admitted or established, laws permit children to inherit from their father's estate unless specifically excluded in his will.
Surrogate motherhood has become one of the most difficult problems in modern family law. The term surrogate mother was first used in connection with in vitro fertilization (see Infertility) in the late 1970s. The newest use refers to the introduction, by artificial insemination, of the sperm of a man whose wife is infertile into a woman who has agreed, often by contract, to bear the child conceived because of the insemination and then relinquish it to the couple after birth.
One argument against surrogacy is that it is little more than formalized baby selling. The counter-argument is that surrogacy is not baby selling because the husband of the couple receiving the child is that child's biological father. Many state legislatures are considering bills that would either make surrogate parenting entirely illegal or strictly regulate it, for example, limiting or prohibiting the payment of fees to the surrogate or to intermediaries. Most would require psychological counselling for the prospective surrogate mother, legal representation for all parties, and court approval of the contract.
CURRENT ABERRATIONS IN PARENTHOOD
There has been a desecration of family values over the centuries, so that today we have un-wed mothers and unfit parents being tolerated in some permissive societies. This is an irresponsible aspect of parenthood. Join in the crusade for campaigning against it. However, since it has become a recurring decimal even in urban cities of Africa, one cannot avoid treating its demerits, in the least, and condemning the immaturity of those who fall prey to such unplanned families that are very disadvantageous to raising good children.
Photo Researchers, Inc./Vanessa Vick
Lesbian Couple and Child
In recent years, gay and lesbian couples have become visible participants in traditional family pursuits. This lesbian couple is raising a son together. This has not reached
Africa for now, and when it does,
it will be regarded as an anathema.
One such aberration is lesbian couples adopting children and raising up such unfortunate children in the absence of parents of both sexes. Of course, such kids will definitely have deformed personality traits and socially, their peers will discriminate against them! They will forever live with the scorn of the community! They may grow up and hate their lesbian ‘parents’ since they were fake ones!
Tony Stone Images/Dan Bosler
In a single-parent family, children live with an unmarried, divorced, or widowed mother or father. In the
, mothers head most single-parent families.
This is an aberration in United States Biafra and most other African countries. In all Africa, offspring of such families are regarded as
‘bastards’ a.k.a. social outcasts. Microsoft
® Encarta ® Encyclopaedia 2004. © 1993-2003
Another similar and in fact the most common aberration is the unwed mother, which is directly the consequence of indiscipline among the youth. Such indiscriminate indulgence in pre-marital sex is an aberration that results in single parenthood, and unfortunately, it is the children that suffer emotionally as their personality will definitely be deformed. Join this team of Happy Family Network crusaders to nip in the bud the laxity in morality that is the remote cause of such aberrations in family life!
If present day parents shirk their responsibilities of being the primary educators of their offspring in matters of morality and social ethics, then we shall have failed in one of the very fundamental duties of responsible parenthood. What legacy will such parents leave for their posterity? Will they be happy to have all their sons and daughters become fathers and mothers without courtship, engagement and formal marriage? We cannot fold our hands and pretend that there is nothing we can do about it!
Contributed By: Robert A. Jensen & Kenez J. Danmbaezue
THE SOCIOANTHROPOLOGICAL STUDY OF FAMILIES
Family as in the science of sociology and anthropology is the basic unit of any social group of humans united through bonds of kinship or marriage, which is present in all societies. Ideally, the family provides its members with protection, companionship, security and socialisation. The structure of the family and the needs that the family fulfils vary from society to society. The nuclear family—two adults and their children—is the main unit in some societies. In others, it is a subordinate part of an extended family, which also consists of grandparents and other relatives. A third family unit is the single-parent family, in which children live with an unmarried, divorced, or widowed mother or father.
Anthropologists and social scientists have developed several theories about how family structures and functions evolved. In prehistoric hunting and gathering societies, two or three nuclear families, usually linked through bonds of kinship, banded together for part of the year but dispersed into separate nuclear units in those seasons when food was scarce. The family was an economic unit; men hunted, while women gathered and prepared food and tended children. Infanticide and expulsion of the infirm that could not work were common. Some anthropologists contend that prehistoric people were monogamous, because monogamy prevails in non-industrial, tribal forms of contemporary society.
Social scientists believe that the modern Western family developed largely from that of the ancient Hebrews, whose families were patriarchal in structure. The family resulting from the Greco-Roman culture was also patriarchal and bound by strict religious precepts. In later centuries, as the Greek and then the Roman civilizations declined, so did their well-ordered family life.
With the advent of Christianity, marriage and childbearing became central concerns in religious teaching. The purely religious nature of family ties was partly abandoned in favour of civil bonds after the Reformation, which began in the 1500s. Most Western nations now recognize the family relationship as primarily a civil matter.
THE MODERN FAMILY
Historical studies have shown that family structure has been less changed by urbanization and industrialization than was once supposed. The nuclear family was the most prevalent pre-industrial unit and is still the basic unit of social organization. The modern family differs from earlier traditional forms, however, in its functions, composition, and life cycle and in the roles of husbands and wives.
Globe Photos, Inc.
During the 1950s, several American television-shows portrayed an idealized middle-class family consisting of a wise breadwinner father, a cheerful and attractive wife, and socially and academically successful children. American actor Robert Young, who starred as Jim Anderson in the series “Father Knows Best,” epitomised the role of all knowing, morally superior husband and father. Here,
is seen surrounded by his loving family, who expectantly await
his interpretation of the world as symbolized by the newspaper story he reads. Anderson
Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003
The only function of the family that continues to survive all change is the provision of affection and emotional support by and to all its members, particularly infants and young children. Specialized institutions now perform many of the other functions that were once performed by the agrarian family: economic production, education, religion, and recreation. Jobs are usually separate from the family group; family members often work in different occupations and in locations away from the home. Education is provided by the state or by private groups. Religious training and recreational activities are available outside the home, although both still have a place in family life. The family is still responsible for the socialization of children. Even in this capacity, however, the influence of peers and of the mass media has assumed a larger role.
Family composition in industrial societies has changed dramatically. The average number of children born to a woman in the
, for example, fell from 7.0 in 1800 to 2.0 by
the early 1990s. Consequently, the number of years separating the births of the
youngest and oldest children has declined. This has occurred in conjunction
with increased longevity. In earlier times, marriage normally dissolved through
the death of a spouse before the youngest child left home. Today husbands and
wives potentially have about as many years together after the children leave
home as before. United States
Some of these developments are related to ongoing changes in women’s roles. Women in all stages of family life have joined the labor force. Rising expectations of personal gratification through marriage and family, together with eased legal grounds for divorce and increasing employment opportunities for women, have contributed to a rise in the divorce rate in the
and elsewhere. In 1986, for instance, there
was approximately one divorce for every two marriages in the United States (see Divorce). United States
During the 20th century, extended family households declined in prevalence. This change is associated particularly with increased residential mobility and with diminished financial responsibility of children for aging parents, as pensions from jobs and government-sponsored benefits for retired people became more common.
By the 1970s, the prototypical nuclear family had yielded somewhat to modified structures including the one-parent family, the stepfamily, and the childless family. One-parent families in the past were usually the result of the death of a spouse. Now, however, most one-parent families are the result of divorce, although some are created when unmarried mothers bear children. In 1991, more than one out of four children lived with only one parent, usually the mother. Most one-parent families, however, eventually became two-parent families through remarriage.
A stepfamily is created by a new marriage of a single parent. It may consist of a parent and children and a childless spouse, a parent and children and a spouse whose children live elsewhere, or two joined one-parent families. In a stepfamily, problems in relations between non-biological parents and children may generate tension; the difficulties can be especially great in the marriage of single parents when the children of both parents live with them as siblings.
Childless families may be increasingly the result of deliberate choice and the availability of birth control. For many years, the proportion of couples who were childless declined steadily as venereal and other diseases that cause infertility were conquered. In the 1970s, however, the changes in the status of women reversed this trend. Couples often elect to have no children or to postpone having them until their careers are well established.
Since the 1960s, several variations on the family unit have emerged. More unmarried couples are living together, before or instead of marrying. Some elderly couples, most often widowed, are finding it more economically practical to cohabit without marrying. Homosexual couples also live together as a family more openly today, sometimes sharing their households with the children of one partner or with adopted or foster children. Communal families, made up of groups of related or unrelated people, have long existed in isolated instances (see Communal Living). Such units began to occur in the
during the 1960s and 1970s as an alternative
life-style, but by the 1980s, the number of communal families was diminishing. United States
All industrial nations are experiencing family trends similar to those found in the
. The problem of unwed mothers—especially very
young ones and those who are unable to support themselves—and their children is
an international one, although improved methods of birth control and legalized
abortion have slowed the trend somewhat. Divorce is increasing even where religious
and legal impediments to it are strongest. Smaller families and a lengthened
post-parental stage are found in industrial societies. United States
Unchecked population growth in developing nations threatens the family system. The number of surviving children in a family has rapidly increased as infectious diseases, famine, and other causes of child mortality have been reduced. Because families often cannot support so many children, the reduction in infant mortality has posed a challenge to the nuclear family and to the resources of developing nations.
As you may have observed, there are variants in the value systems now attached to the marriage institution in general and family life in particular. What used to be sacred is no more held in high esteem! Who, in the Victorian age would imagine that two women would live as husband and wife, knowing fully well that they could never have children by themselves, they go ahead to adopt some else’s child and rear as their own! Who would even consider allowing such unfit ‘parents’ adopt his/her child? There has been a lot of desecration of family values. We at the NGO, HAPPY FAMILY NETWORK INTERNATIONAL are committed to reversing these obnoxious trends! Please assist us by at least instructing your friends and your children to see these aberrations for what they truly are. They are the demonic attack on the sanctity of marriage and exemplary family lifestyles! If we all undertake to educate adolescents near us, we can succeed. Don’t sit on the fence. Join in the crusade!
Contributed By: Ida Harper Simpson & Kenez Jideofo Danmbaezue
A TYPICAL AFRICAN VIEW OF FAMILY LIFE
In the traditional African community, all the descendants of one great ancestor live and cater for each other in the now famous “AFRICAN EXTENDED FAMILY SYSTEM.” In this system, the concept of nuclear family is foreign as everyone is everybody’s concern and everybody’s keeper. Democratic decisions submit to patriarchal ones, as elders have the final say at a communal meeting. “Custom, then, is the great guide of human life,” wrote Scottish philosopher David Hume. Knowing the customs of a country is, in effect, a guide to understanding the soul of that country and its people. The following Sidebar is intended to provide a glimpse into the unique world of this nation’s customs: how people marry, how families celebrate holidays and other occasions, what people eat, how they socialize and have fun.
MARRIAGE AND FAMILY CUSTOMS OF
REPUBLIC OF THE CONGO
Traditionally, marriage is a family affair and is at least partly arranged by parents. Among matrilineal families, the preferred marriage partner is a cousin—one of the mother’s brothers’ children. However, that pattern is slowly changing, especially in urban areas.
Although family structure varies greatly among the different ethnic groups, much emphasis is placed on group goals and overall family welfare. Large extended families are normal, and they usually live under the same roof or in a tight group of homes. In the western region of
(DRC), families are mostly matrilineal, with the mother’s brother as the male
with the greatest authority in the family, rather than the husband. In other
areas of the country, patriarchal and polygamous families, as well as
combinations of these, are common. Urban families, particularly among the more
affluent, are usually patrilineal and tend to include fewer relatives in the
extended family. Democratic
Republic of the Congo
Funerals for family or close friends are often elaborate events. Practices vary, but the family of the deceased usually announces a period of mourning at a large gathering of family and friends. These gatherings involve singing, dancing, speeches, and crying into early morning hours. At the end of the designated period, typically 40 days, the mourning is lifted at a large, sometimes lavish celebration. Friends and family attend this event to show their concern for the immediate family of the deceased. These funerals also serve as an important means to maintain personal, romantic, and professional contacts.
Panos Pictures/Marcus Rose
In some societies, the extended family is the most common unit of social organization. This Pakistani family consists of three generations of relatives who live together.
Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003
Staple foods include cassava, rice, potatoes, bananas, yams, beans, maize, fish, groundnuts, and various other fruits and vegetables. One of the most common foods is fufu, a mealy paste made from flour and water. Known by a variety of names in different parts of the country, fufu is typically served with a sauce made from tomatoes or peanuts. Another popular food is shikwanga, a dish from the western regions of Congo (DRC) that is made from manioc flour and water. Sauces are served with most meals. Palm oil sauces are especially common, and most sauces are prepared over a wood or charcoal fire, even in urban areas. Common fruits include mangoes, oranges, papaws, and coconuts. Some types of food must be purchased daily because people do not have ways to keep them fresh. As a result, of years of political crisis and the breakdown of many services, adequate supplies of food are failing to reach some areas.
Eating customs vary widely. Silverware is very common in urban areas, but people often eat with their hands in rural areas. People usually eat with the fingers of the right hand only. Men and women sometimes dine separately, washing their hands in bowls of warm soapy water at the end of the meal. Portions may be served individually or in a communal bowl depending on local custom. When sharing a bowl, people eat only from the part directly in front of them. Only the eldest distribute meat to those eating the meal.
In urban areas, men and women generally shake hands and smile when greeting. The French term Bonjour (“Good day”) is used among many people in urban areas, but among Lingala speakers, Mbote (“Hello”) is more common and is followed by Sango nini? (“What’s new?”).
In rural areas, men do not usually shake hands with women, but will with other men. Some rural women greet men by clapping their hands a few times and bowing slightly. In some areas, men greet each other by gently touching the side of the forehead—much like the European custom of kissing cheeks—during a handshake. In the eastern and south-eastern parts of the country, the Swahili greeting Jambo (“Hello”) is common.
Other greetings vary according to ethnic group. In virtually all parts of the country, greetings are more elaborate and lively than goodbyes.
Visiting is important. Family and close friends often drop by unannounced, but strangers are expected to make arrangements in advance. People often socialize in outdoor courtyards rather than inside homes. Socializing indoors is reserved for special events, usually occasions when the guests are of a markedly higher social status than the hosts. When a person first pays a visit, a gift is not appropriate. Guests may give small gifts, such as food or an item for the house, after they establish a relationship.
First-time visitors are directed where to sit by the hosts, and the guests generally remain seated. Good friends and members of the extended family have greater liberty to make themselves at home. If children are present, they are expected to greet each adult with a handshake and perhaps a kiss on the cheek. They are then usually dismissed while the adults socialize.
If a host offers to share a meal, the guest should first show reluctance to join the host’s table before finally accepting the offer. It is important to try at least some of the food as a gesture of goodwill. In Biafra, refusal to eat a morsel might be misinterpreted as social status consciousness or pride!
Soccer is the most popular sport in Congo (DRC). Rural inhabitants enjoy gathering to dance and play drums. Many urban people spend their leisure time socializing, dancing, or listening to local jazz.
HOLIDAYS AND CELEBRATIONS
- Public holidays include New Year’s Day (1 January);
- The Commemoration of the Martyrs of Independence (4 January);
- Easter; Labour Day (1 May);
- Promulgation of 1967 Constitution and Day of the Fishermen (24 June);
- Independence Day (30 June);
- Parents’ Day (1 August); and
- Youth Day (14 October).
- Veterans Day is observed on 17 November and
- Anniversary of the Second Republic on 24 November.
- Christmas Day is celebrated on 25 December.
Source: Encarta Interactive World Atlas
Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003 Microsoft Corporation. All rights reserved.
What has been described above, with only minor alterations, can apply to most of the communities along the West Coast of Africa. The Popular African Extended Family System takes child rearing as everybody’s business. In Biafra, especially for the Igbo ethnic group: “A Child is owned by the Community.” The initiation rites for teenage boys and the rites of passage for the girls at menarche ensure the inculcation of the norms and mores of the community. Every adult has an obligation towards the child in danger as well as the erring child. Our people say: “An adult does not stay at home and a pregnant goat delivers while still tied up with a rope!” Again, we say: “One does not chase rats while one’s homestead is on fire.”
In the traditional setting, every child helps an elder carry his loads, stands up so that an older person can have a seat, rune errands enthusiastically, and is polite even to strangers! Unfortunately, this code is disappearing due to westernisation, urbanisation and the anonymity associated with township life! The competing religious groups and their discriminatory rules do not help matters! The overwhelming influence of partisan politics, class-consciousness ethnocentric stereotypes, fanatical religio-cultural attitudes and other forms of, social prejudice is quite palpable. The arrival cellular phones, the Internet and other mass media gadgets compound this hopeless state of degeneration of values, once held sacrosanct by our traditional religion, norms and mores!
Dr & Mrs. Jideofo Kenechukwu Danmbaezue
Chief & Lolo Emmanuel Agha Mbey
Sir & Lady Andrew Okoliukwu Okeukwu
GENETIC COUNSELLING BEFORE WEDDING
Genetics is the science of inheritance and a specialty in Zoology. In the medical field its research results have been appropriated to predict health problems that newly weds and their offspring might experience after they might signing on the dotted lines. It is worth the while of every intending couple to avail themselves of our services in this prophylactic approach to marital counselling. You can forestall many headaches and heartaches by listening to our advice. Do not place your children’s health in jeopardy!
Genetic Counselling is the medical specialty that helps parents and prospective parents evaluate and cope with their risk of passing hereditary disorders to their children. Genetic counselling also helps individuals assess the possibility that they will get a medical condition known or suspected to have a genetic basis, such as Huntington’s disease, breast cancer, or Alzheimer’s disease.
Photo Researchers, Inc./Omikron/Science Source
Sickled Blood Cell
The curved, crescent-shaped blood cell (bottom, left) signals the presence of sickle-cell anaemia, a genetic disorder that affects about 72,000 people in the United States, primarily African Americans. It is usually caused by a genetic mutation, thus this type of anaemia results from abnormal haemoglobin, the oxygen-carrying component of red blood cells, which distorts the shape of blood cells after they have released oxygen. The sickled cells cannot pass smoothly through tiny blood vessels. The resulting blockages cause intense pain to the sufferer, often in childhood, and serious deficiencies of oxygen and other blood nutrients throughout the body. Most carriers die before their twenty-first birthday
Hafani Organisation & Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003
In developed countries, at least 1 infant in every 100 is born with a disorder caused by an alteration in 1 or more of the estimated 50,000 human genes. In third world countries, the figure is higher. Genes are segments of deoxyribonucleic acid (DNA), the hereditary molecule found in the chromosomes of cells. The severity of genetic disorders varies from mild conditions such as colour blindness to serious diseases such as Duchenne muscular dystrophy and Tay-Sachs disease. In most cases, a team of health experts at a medical centre provides genetic counselling. The team typically consists of counsellors who have graduate training in genetics, psychology, population statistics, and medical education, along with physicians who have advanced training in human genetics. The team also may include nurses, social workers, and psychologists who have specialized skills in patient education and public health.
Genetic counselling may involve more than one visit between a counsellor and a client, who may be an individual, a couple, or an entire family. During the first visit, the counsellor gathers information about the client’s family medical history. The counsellor may discuss options for diagnostic tests that could help determine if a person is at risk for passing an inherited disorder on to children or is susceptible to a particular genetic disease.
After considering these options, the client may choose to undergo testing at that time or in a follow-up session. When testing is completed, the genetic counsellor analyses the family history and test results to determine whether a genetic disorder exists within a family and, if so, how it is inherited. The good counsellor then discusses those conclusions with the client. Genetic counsellors help the client cope with the emotional repercussions of the diagnosis as well as any practical concerns. Genetic counsellors respect the privacy of the individual and family, keeping all information exchanged during counselling sessions confidential. Every parent-to-be who fails to do this is irresponsible and not worthy of the appellation!
BENEFICIARIES OF GENETICAL COUNSELLING
Many prospective parents use genetic counselling to help resolve issues surrounding pregnancy and infertility. Genetic counselling is helpful to parents who already have a child with a genetic disorder so they can learn more about the condition and the chance that their other children may be affected. People with a family history of life-threatening diseases may consult a genetic counsellor to learn the probability that they will develop a disease. Others seek genetic counselling to determine the likelihood that they will develop a disease that occurs more frequently in their ethnic group.
A couple that is thinking about conceiving a child may want to consider genetic counselling for several reasons. For instance, many women aged 35 or older seek genetic counselling because they are at a higher risk than younger women of giving birth to a child with a chromosomal abnormality. These abnormalities occur when a child inherits all or part of an extra copy of a chromosome. Down syndrome, the most common chromosomal disorder, is almost nine times more common in babies born to women aged 40 than those born to women aged 30. Couples who already have a child who was born with a genetic disorder may seek genetic counselling to determine the risk that future children may be similarly affected.
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Recessive Gene Transmission
Some genes that cause genetic diseases interact in a dominant-recessive pattern. In these cases, two copies of the recessive gene are required for the disease to occur. A person who has just one copy of the recessive gene is termed a carrier, since he or she carries the gene but is not affected by it. In the illustration above, the dominant gene is represented in green, and the recessive in blue. For the couple on the left, the father has one copy of the dominant gene and one copy of the recessive gene. The mother has two copies of the dominant gene. Each parent can contribute just one gene to the child. The four children showed on the lower left represent the probabilities (not the actual children) for the combinations that can result from their parents. The children on the far left received the recessive gene from their father and the dominant gene from their mother, and are therefore carriers. For any child born to these parents, there is a 50 percent chance that the child will be a carrier. Since none of the children can inherit two copies of the recessive gene, none of the children will develop the disease. When both parents are carriers, however, as shown by the couple on the right, there is a 25 percent chance that any child born has the disease, a 50 percent chance that a child is a carrier, and a 25 percent chance that a child does not have the disease and is not a carrier.
Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003
Expecting couples concerned about the health of their unborn baby may request genetic counselling to learn if the baby is at risk for a disease. A pregnant woman may worry that she has been exposed to factors that can hurt the development of her foetus, such as infectious diseases, medications, alcohol, non-medical drugs, or radiation. Genetic counselling can prove useful when adopting a child. Parents interested in adopting a child whose biological parent or grandparent has an inherited condition may seek counselling to determine if this family history is likely to affect the child.
The parents of a newborn diagnosed with a genetic disease may ask a genetic counsellor to explain the progression of the disease and describe the types of treatments required to keep their baby healthy. Infertile couples or those who have experienced two or more miscarriages may pursue genetic counselling to learn whether a genetic condition may be responsible for their reproductive difficulties.
People with a Family History of Disease
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Family pedigrees trace specific genetic characteristics through three or more generations. Pedigrees such as this one, which depicts the inheritance of a gene associated with cystic fibrosis, help genetic counsellors to identify, which individuals in a family are at risk of either inheriting a genetic disorder or being a carrier for a disorder. Whereas only Africans have the Sickle Cell disease, mixed marriages could produce a variety of mutations that we are still researching into. Colour blindness, on the other hand is not common in and their descendants Africans!
Hafani Organisation & Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003
Genetic counselling can also help people who have a family history of common diseases, such as cancer, heart disease, or mental illness. Although these diseases are not routinely considered genetic disorders, they often have a hereditary component when they affect multiple members of a family. A genetic counsellor may recommend that family members set up regular physical examinations or screening tests with a medical specialist. These regular examinations can detect health problems early, when the conditions may be easier to treat. Counselling may also help family members make informed decisions about diet, exercise, and surgery options that can help reduce the chance that the condition will develop, or that can lessen the condition’s severity.
Ethnic Groups at Higher Risk for Disease
Some people seek genetic counselling to learn about genetic disorders that occur more frequently in their ethnic group. For instance, Tay-Sachs disease is more common among certain populations of Jews from eastern Europe, and sickle-cell anaemia occurs primarily in African Americans.
DIAGNOSING A GENETIC CONDITION
The genetic counsellor’s top priority is to help accurately diagnose a genetic condition. In some cases, clients may be referred to a counsellor after a physical examination or medical tests suggest an inherited disorder. In this case, the counsellor must evaluate the reliability of the diagnosis and determine if additional tests or second opinions from medical specialists are needed to confirm it. In other instances the counsellor may aid in making the initial diagnosis by arranging special tests, such as blood tests that determine the presence of a disease-causing gene or chromosomal abnormality, or prenatal screening (such as an ultrasound) that evaluates the health of a foetus.
As part of the diagnosis process, genetic counsellors educate clients about the inheritance patterns of suspected genetic disorders, many of which are rare conditions unfamiliar to most people. Genetic disorders typically arise from single gene mutations or chromosomal abnormalities that are transmitted from generation to generation.
Each individual inherits two versions of every gene, one from the mother and one from the father. Occasionally one gene in a pair becomes altered through a process called mutation, and this mutated gene passes from parent to child in a predictable pattern. In some cases, the mutated gene inherited from one parent dominates, expressing itself even when a normal gene inherited from the other parent is present. A parent who has the mutated gene develops the disease and has a 50 percent chance of passing the faulty gene on to his or her child. Examples of diseases caused by dominant genes include neurofibromatosis and Huntington’s disease.
Recessive genes, such as sickle-cell anaemia and cystic fibrosis, cause other diseases. Such diseases develop when both genes of a pair have a mutation. Two parents who each carry a mutated recessive gene for the same disease have a 25 percent chance with each pregnancy of having a baby who will develop the disease. A parent may unknowingly carry a mutated recessive gene for a particular disease without suffering any symptoms of the disorder.
Single gene mutations may occur on the sex chromosomes, the pair of chromosomes in each cell that determine the sex of an individual. Females’ sex chromosomes consist of two X chromosomes, and males have one X and one Y chromosome. A female with a recessive mutated gene on one X chromosome usually has a normal gene on her other X chromosome, and the normal gene masks the effects of the mutated gene. As a carrier of the mutated gene, the female has a 50 percent chance of passing the mutated gene on to her children. Daughters who inherit the altered gene are usually unaffected because they have a normal gene on their other X chromosome. But when a male inherits a mutated gene on the X chromosome from his mother, he does not have a normal second copy of the gene on the Y chromosome to mask the effects of the mutated gene. Diseases that result from such X-linked gene mutations include haemophilia and Duchenne muscular dystrophy.
Chromosomal abnormalities affect the number of chromosomes, the size or appearance of certain chromosomes, or the arrangement of chromosomes in cells. One example of a disease associated with the presence of an extra chromosome is Down syndrome, which causes mental retardation and physical abnormalities.
Turner syndrome, a condition that affects females, results when one of the two X chromosomes is partially or completely missing. In some cases, a healthy parent may carry a chromosomal rearrangement, known as a translocation, in which a piece of one chromosome is attached to another.
Another abnormality, known as inversion, occurs when a piece of chromosome gets turned around 180 degrees from its normal position. People who have chromosomal rearrangements may experience infertility or repeated miscarriages.
Family Medical History
Genetic counsellors gather information about a client’s family medical history to determine if an inherited disorder exists within a family. Genetic counsellors record a client’s medical family history for at least three generations and present the information as a diagram, called a pedigree.
A pedigree uses symbols to form a family tree—circles represent females, squares indicate males, and horizontal and vertical lines connect the circles and squares to show how family members relate to each other.
The pedigree details significant family and health information for each family member, including birth and death dates, cause of death, miscarriages, stillbirths, and medical conditions, such as cancer, diabetes, heart disease, birth defects, genetic conditions, and mental retardation.
Pedigrees also note the ethnic, racial, or geographic origins of the client’s ancestors to alert the counsellor to genetic disorders prevalent among certain groups of people.
SOME GENETIC DISORDERS DETECTED PRE-NATALLY
Genetic disorders may result from defects in genes or from chromosomal abnormalities. Prenatal tests, performed early in a woman’s pregnancy, can identify a foetus with a genetic abnormality.
Prenatal diagnosis using amniocentesis or Chorionic villus sampling pose a slight risk to the foetus, and health professionals generally recommend these tests only if the mother or father has a family history of a genetic disorder or an increased risk of having a child with a chromosomal abnormality.
Congenital adrenal hyperplasia
10 per 100,000 people
31 per 100,000 live Caucasian births;
11 per 100,000 live Hispanic births;
7 per 100,000 live African American births;
3 per 100,000 live Asian births
Duchenne muscular dystrophy
20 to 30 per 100,000 males
20 per 100,000 male live births
10 per 100,000 people
Polycystic kidney disease (adult type)
100 to 250 per 100,000 people
250 per 100,000 African Americans
28 per 100,000 Ashkenazic Jews worldwide;
28 per 100,000 Cajuns
1 per 100,000 people in North and South America
*Incidence rates are for populations most affected in the United States.
Microsoft ® Encarta ® Encyclopaedia 2004. © 1993-2003
Genetic counsellors use a family medical history to identify patterns of disease inheritance and to predict the probability that other family members will inherit a disease. A family medical history may also identify the causes of diseases that do not have a genetic basis. Disease may occur among individuals who share a certain lifestyle habit, such as smoking cigarettes or excessive use of alcohol.
Genetic counsellors may suggest that a client undergo certain tests that can analyse the genetic information in a person’s cells. Some tests can help identify individuals who carry genes for recessive genetic disorders. Other tests can identify disease-causing genes or chromosomal disorders in a foetus. Some tests can determine if a person has a high probability for developing an inherited disorder later in life.
Carrier screening tests can determine if an otherwise healthy person carries a recessive gene for a disease that is common in certain ethnic groups, such as Tay-Sachs disease in Jews from Eastern Europe. The client usually provides a blood sample or a sample of cells scraped from the inside of the cheek. These cells are examined in a laboratory to determine if the person has a mutated gene. Such screening helps parents make reproductive choices.
In cases in which a woman is already pregnant and concerned for the health of her baby, genetic counsellors may suggest that she undergo prenatal tests that can identify health problems in the foetus. For the great majority of mothers, who have normal test results, prenatal testing reassures that the foetus is healthy. If prenatal tests indicate that a foetus has a disorder, genetic counsellors provide parents with information about the disease as well as the medical and educational needs of children who have the disorder. Counsellors can also help parents determine if the option to terminate a pregnancy is in harmony with the couple’s values.
Physicians use several methods to diagnose genetic abnormalities in a foetus. Ultrasound imaging uses sound waves to create an image of the foetus. Ultrasound monitors the growth and development of the foetus and can identify abdominal wall defects, cleft lip, and some heart defects. A blood test can identify whether a mother’s blood contains a high level of the protein alpha-fetoprotein, an indication that the baby is at risk for spinal cord abnormalities.
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Two types of medical tests may be used early in a woman’s pregnancy to determine if her foetus has a defective gene or a chromosomal abnormality. Both procedures remove cells surrounding the developing foetus. The cells obtained have the same genetic makeup as the foetus and can be tested for genetic abnormalities. In Chorionic villus sampling, a doctor removes tissue from the Chorionic villi, finger-like projections that are part of the developing placenta, between 10 and 12 weeks of pregnancy. Using ultrasound guidance, the doctor inserts either a needle through the woman’s abdominal wall or a thin, hollow tube called a catheter through her cervix to reach the Chorionic villi. Using a syringe the doctor suctions out cells. Amniocentesis is usually performed between 15 and 17 weeks of pregnancy. In this procedure, a doctor uses ultrasound guidance to insert a needle through the abdominal wall into the amniotic fluid surrounding the foetus. Cells from the amniotic fluid are removed using a syringe. Both procedures pose a slight risk for the developing foetus, and health professionals recommend these tests only in cases in which a mother or father has a family history of a genetic disorder or a known risk for chromosomal abnormalities.
Microsoft ® Encarta ® Encyclopaedia
Chromosomal analysis is performed on foetal cells, usually when the mother is over age 35 and therefore most at risk for bearing a child with chromosomal abnormalities. Chorionic villus sampling analyses the cells from the placenta, the organ that supplies nutrients and oxygen to the foetus and removes waste. Testing performed on cells from the amniotic fluid, the protective liquid that surrounds the foetus in the uterus, is known as amniocentesis.
A genetic counsellor may recommend that the mother undergo percutaneous umbilical blood sampling (PUBS). In this test, a small blood sample is removed from the umbilical cord of the foetus. From that sample, a physician can identify certain blood diseases and other disorders that prevent normal foetal growth.
Genetic counsellors may assist clients in decisions about predictive testing, which identifies if a person has one or more altered genes whose effects typically do not appear until later in life. There are two types of predictive testing: pre-symptomatic tests and susceptibility tests. When an individual’s parent or grandparent develops an illness such as Huntington’s disease, the individual may fear developing the same disease later in life. In such a case, a genetic counsellor may arrange for the client to undergo pre-symptomatic testing, which analyses DNA in the blood to determine whether the person has the altered gene that causes Huntington’s disease. If the altered gene is present, the genetic counsellor can predict with certainty that the client will develop Huntington’s disease. However, predictive testing cannot predict the age a person will develop the disease.
Before recommending that clients undergo pre-symptomatic testing, a genetic counsellor prepares clients to accept the test results. Many diseases that develop late in life cause severe disability or lead to premature death. Clients must be prepared to live with the knowledge that they could eventually develop a fatal disease. Some people choose not to have testing, while others prefer to know their risk so that they can make decisions about having children or make financial or care-giving arrangements before symptoms develop.
Susceptibility tests determine the presence of a gene or group of genes that may predispose a person to develop a particular health problem later in life. Unlike pre-symptomatic tests, these tests only identify a higher probability that a particular disorder will develop. They do not provide a certain diagnosis. Susceptibility tests may reveal a risk for some types of cancer, heart disease, diabetes mellitus, and Alzheimer’s disease. If a woman learns that she has a gene closely linked to breast cancer, a genetic counsellor can refer her to a breast cancer specialist who can monitor the woman’s health. If the woman does develop cancer, the close monitoring will enable the specialist to detect it in its earliest stages, when the disease is easiest to treat.
CHOOSING A COURSE OF ACTION
After identifying a disease or estimating the probability that a disease will develop, the genetic counsellor helps individuals and their families choose a course of action to cope with the genetic condition. Genetic counselling requires sensitivity to a client’s needs and belief systems. Individuals have varying life experiences, social attitudes, and religious values that will influence their thinking about testing and medical issues. For example, a couple may not mind coping with the disabilities of a child with an inherited disease, or their religious values may prevent them from considering abortion. These couples may decide against prenatal testing. In other cases, a couple who has already had a child with a terminal illness may not want to have any more children. The couple may choose to undergo sterilization procedures that will permanently prevent pregnancy.
Keeping these differing views in mind, genetic counsellors do not tell a client what to do. Instead, they use what is known as a nondirective approach. If a client asks a genetic counsellor, “What would you do if you were me?” the counsellor may reply, “Other individuals in your situation have considered the following options...” This neutral response ensures that the client controls decision-making.
Genetic counsellors help their clients take action to deal with the immediate or potential challenges presented by a genetic disorder. This may include helping couples that do not want a child choose a contraceptive option or arrange for sterilization surgery.
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Correcting Genetic Diseases
Gene therapy may someday be able to cure hereditary diseases, such as haemophilia and cystic fibrosis, which are caused by missing or defective genes. In one type of gene therapy, genetically engineered viruses are used to insert new, functioning genes into the cells of people who are unable to produce certain hormones or proteins necessary for the body to function normally.
Counsellors may help infertile couples find an adoption agency. Genetic counsellors may act as consumer advocates, helping families find community resources, such as special education programs for children born with genetic disorders that cause learning disabilities. They develop strategies to provide round-the-clock care for a person with a severely disabling condition. In addition to practical considerations, counsellors address the emotions of parents faced with the devastating news that their child has a deadly illness or of siblings who do not have a disorder themselves but may be troubled by the problems facing other family members. Through such efforts, genetic counsellors help families make the best possible adjustment to the physical, economic, social, and emotional burden of the disorder.
Contributed By: Robin L. Bennett, Chris A. Ezike & Nkechi N. Mbaezue
GENETIC ENGINEERING AND ITS USE IN MEDICINE
Genetic Engineering is the alteration of an organism's genetic or hereditary material to eliminate undesirable characteristics or to produce desirable new ones. Genetic engineering is used to increase plant and animal food production; to diagnose disease, improve medical treatment, and produce vaccines and other useful drugs; and to help dispose of industrial wastes. Included in genetic engineering techniques are the selective breeding of plants and animals, hybridisation (reproduction between different strains or species), and recombinant DNA.
Production of Medicines
In 1982, the United States Food and Drug Administration (FDA) approved for the first time the medical use of a recombinant DNA protein, the hormone insulin, which had been cloned in large quantities by inserting the human insulin gene in Escherichia coli bacteria. Previously, this hormone, used by insulin-dependent people with diabetes, had been available only in limited quantities from hogs. Since that time, the FDA has approved other genetically engineered proteins for use in humans, including two cloned in hamster cell cultures: Tissue plasminogen activator (tPA), an enzyme used to dissolve blood clots in people who have suffered heart attacks, and Erythropoietin, a hormone used to stimulate the production of red blood cells in people with severe anaemia.
Scientists also have employed recombinant DNA techniques to produce medically useful human proteins in animal milk. In this procedure, the human gene responsible for the desired protein is first linked to specific genes of the animal that are active only in its mammary (milk-producing) glands. The egg of the animal is then injected with the linked genes. The resulting transgenic animals will have these linked genes in every cell of their body but will produce the human protein only in their milk. The human protein is finally extracted from the animal's milk for use as medicine. In this way, sheep's milk is used to produce Alpha-1-antitrypsin, an enzyme used in the treatment of emphysema; cow's milk is used to produce Lactoferrin, a protein that combats bacterial infections; and goat's milk is used as yet another way to produce tPA, the blood-clot-dissolving enzyme also cloned in hamster cell cultures.
Recombinant DNA technology also is used in the production of vaccines against disease. A vaccine contains a form of an infectious organism that does not cause severe disease but does cause the body's immune system to form protective antibodies against the organism. When a person is vaccinated against a viral disease, the production of antibodies is actually a reaction to the surface proteins of the coat of the virus. With recombinant DNA technology, scientists have been able to transfer the genes for some viral-coat proteins to the vaccinia, or cowpox, virus, which was used against smallpox in the first efforts at vaccination, and which gave the process its name. Vaccination with genetically altered vaccinia is now being used against hepatitis, influenza and herpes simplex viruses. Genetically engineered vaccinia is considered safer than using the disease-causing virus itself and is equally as effective.
Gene therapy is a medical management of a patient in which a healthy gene can be directly inserted into a person with a malfunctioning gene. This is perhaps the most revolutionary and promising of recombinant DNA technology, but many problems remain to be solved in getting the healthy gene into human cells. Although the use of gene therapy has been approved in more than 100 clinical trials for diseases such as cystic fibrosis, emphysema, and muscular dystrophy, there have yet been no cures.
Public reaction to the use of recombinant DNA in genetic engineering has been mixed. The production of medicines using genetically altered organisms has generally been welcomed. However, critics of recombinant DNA fear that the pathogenic, or disease-producing, organisms used in some recombinant DNA experiments might develop extremely infectious forms that could cause worldwide epidemics. In an effort to prevent such an occurrence, the National Institutes of Health (NIH) has established regulations restricting the types of recombinant DNA experiments that can be performed using such pathogens.
Transgenic plants also present controversial issues. Environmentalists fear that the transgenic plants could spread and eliminate existing species. In addition, it has now been proved that allergens (see Allergy) can be transferred from one food crop to another through genetic engineering. In an attempt to increase the nutritional value of soybeans, a genetic engineering firm experimentally transferred a Brazil nut gene producing a nutritious protein into the soybean plant. However, when a study found that the genetically engineered soybeans caused an allergic reaction in people sensitive to Brazil nuts, the project was cancelled. Questions also have been raised concerning the morality of producing transgenic organisms. In addition, some critics object to the patenting of genetically altered organisms because it makes the organisms the property of particular companies.
The lack of a completely successful gene therapy programme has concerned many people, including a number of scientists. Medical scientists, in particular feel that before additional clinical trials are conducted, more must be understood about the factors that control whether a particular vector can enter a given type of cell and become incorporated into its genetic material. However, the wishes of many people awaiting gene therapy, as well as the commercial interests of companies, have created great pressure both to continue existing programmes and to begin new ones. The current challenge posed by HIV/AIDS is a case in point, demonstrating the urgent need to continue the search for effective remedies.
Contributed By: Louis Levine and Kenez Danmbaezue
FOR HAFANI PROJECT 007 @ UNTH, ENUGU on HIV-MANAVEN 2001 – 2003.