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Healthy genotype and heredity
Health and healthy way of life-> the Body and reason
In each family discuss heredity problems. Considering a family album, we usually are not surprised, that children are similar to the parents and more remote ancestors. Sometimes it is the identical form of a nose which are a family sign. In other cases this structure of the person, the form of auricles, a hair colour or an eye. This similarity becomes especially amazing when we meet twins. How many surprising histories are connected with this natural phenomenon. We can be surprised, but at the same time understand, that anything surprising in it is not present are displays of a heredity. However it is not enough these data for the modern person, it should, at least in general, to represent, what image with what help of the mechanism these lines of similarity from generation to generation are transferred. It is important to understand, that origin of a new life and formation of a germ of the person is caused by that there is absolutely certain mechanism of transfer of the hereditary information. It is concentrated in sexual cages of the future parents, namely in chromosomes.
For the healthy person свойствен a set from 46 chromosomes, the floor is defined by presence of so-called sexual chromosomes: X or U.Tak the chromosomal complement for the man makes 46, ХY, and a sexual set of the woman 46, ХХ. The sexual cages participating in fertilisation, contain половинный a set, and the mechanism of formation of the child man's or female looks so
From this simple scheme it is visible, that half of hereditary material of mother (23) and half of hereditary material of the father (23) merge and form, a full hereditary set of 46 chromosomes. If from mother the future child always receives only Ххромосому (as to it свойствен a set 46, XX), from the father it can sometimes receive Ххромосому (then X mothers + X father will be the basis for a birth of the girl), and sometimes and Yхромосому. The combination of a chromosome X with chromosome Y always testifies to an accessory to a male.
Each person, especially young, marrying, should know, that illnesses are by right of succession transferred to posterity not only external lines of similarity, but also the signs defining both health, and. Usually each person or receives these data in the family, or learns from people surrounding it. They concern those families where in several generations there are same diseases. For example, mental, illnesses of a metabolism, disease of a skin, etc. However happen also such families where only the child has hereditary disease, and its parents are healthy. In these cases especially often there are puzzled questions: it cannot be because we in a family do not have patients with congenital illnesses.
This question demands more detailed explanations.
The chromosomes which are settling down in a kernel of each cage, by their consideration by means of a microscope remind thin threads. Each chromosome consists of set of the small particles reaching of several millions and known under name "genes". Therefore the science studying problems of a heredity, also has received the name "genetics". Genes are carriers of the hereditary information. It under their control occurs growth and germ and fruit development, it thanking their control in a human body are difficult processes of a metabolism. Hence, health of the person depends on their "health" also. Quite often there are such situations when under the influence of damaging factors there are rough changes in the chromosomal device: the quantity of chromosomes (instead of 46 — 47 increases or decreases or 45), there is their rupture, etc. Thus there are rough deviations in a state of health, and diseases concern group of chromosomal illnesses. They are accompanied by developmental anomalies of a brain, heart and vessels, bronchial tubes and lungs, kidneys and a skeleton and other bodies and systems. There are such situations, and they meet much more often when the chromosomal device of a cage ostensibly has no changes. However changes arise at level of genes — the smallest particles which are a part of chromosomes. These illnesses when there is a congenital defect of the gene which is responsible for certain process or a sign in a human body, have received the name of gene illnesses. The big group of diseases at which gene defect leads to infringement of a metabolism and in the subsequent to occurrence of many heavy frustration concerns them: nervous system, hearing, debate, опорнодвигательного the device, to skin illnesses, etc.
Along with it it is allocated groups of diseases at which interaction of many genes is broken, that also it is reflected in a state of health of the person and leads to development of so-called polygene diseases: to a bronchial asthma, hypertensive illness, a diabetes and so forth
In such cases it is accepted to speak about so-called hereditary predisposition of the person. Congenital weakness какойлибо systems of the person thus is meant. It is shown (i.e. There is an illness) only at the provoking moments (stress, a trauma, infections, intoxications, an overeating etc.). So, for example, the diabetes can sharply develop at the person after a stressful situation or at immoderation in a food (at adiposity). Hence, each person should remember, the role of hereditary factors to a condition of its own health is how much important. Members of a family and, of course, posterity. Unfortunately, modern people underestimate necessity of this knowledge, and it is shown first of all in very poor data on the relatives, and furthermore relatives removed on time. At большей population parts these data are limited тремячетырьмя to generations:
In this family tree consisting of 4 generations, the sick child — the girl (I1), her father II3, the grandfather in the area of father III1, great-grandfather IV1 etc. Having looked at this family tree, it is possible to pay attention, that all conditional designated relatives of the sick child ostensibly are healthy, their small squares (a male symbol) and circles (a female symbol) are absolutely pure. Only the symbol of the child (11) is noted by black colour. If the person knows and loves the relatives, it has from them many very valuable data and then the family tree as though revives. It testifies not only to character of related communications, but also about age, a state of health etc. For example, the father of the child (II,) suffers a diabetes, mother of the child is healthy (П2), the grandfather in the area of the father (III,) is sick of a diabetes etc. Getting acquainted with such family tree, you start to understand, that in this family there is a certain hereditary predisposition to disease by a diabetes.
These data are especially important for the pregnant woman. The pregnant woman having hereditary predisposition to a diabetes, has a real threat for a fruit. On it in the course of pre-natal development can have harmful influence of infringement of a carbohydrate exchange. Pregnancy can spontaneously interrupt or come to the end with a birth of a "huge" fruit with weight of a body more than 4,5 kg and growth more than 50-55 see Thus, naturally, difficulties are possible at sorts and a trauma of the newborn.
At family tree drawing up it is possible to explain and understand, why in a family not all suffer the same illness, but only one patient while parents are healthy. This results from the fact that there are various variants of inheritance of the signs defining both a state of health, and illnesses. There are diseases at which their inheritance from posterity in posterity is transferred as speak, on a vertical (patients I1, II1, III1, IV1,) — аутосомнодоминантный inheritance type.
Such family tree does not cause puzzled questions, it brightly shows, that in a family there are diseases which are descended. It is much more difficult to agree with existence of hereditary illness at the child if parents and its other relatives are healthy. Unfortunately, such situation meets often, and it arises at аутосомнорецессивном transfer type. Thus parents, really, are healthy, but they are carriers of the same "sick" gene. It is possible to see it on other scheme, on which sick the child (I1,) is designated by an arrow and a dark small square, and its healthy, but parents being carriers (П1,2) a small square and a circle shaded half. When incorporate identical половинки the basis for illness is created.
To such diseases which are as though transferred across, such hereditary diseases of a metabolism, as фенилкетонурия and галактоземия (intolerance of parent milk) concern, for example.
The author had to observe such families. The young married couple which very much wished to have children, but each time pregnancy and a birth of outwardly healthy child soon was especially remembered came to an end with its destruction. Special researches have shown, that children suffered intolerance of chest milk. The corresponding measures including both treatment of the woman during pregnancy, and its again born child have been taken. In a young family there was the healthy child which development proceeded normally.
Data on harm of related marriages should be very important information for the young men marrying. Such marriages have been caused by the different reasons. Sometimes it has been connected with absence of a marriage choice, it concerned the population of small remote villages where the groom and the bride owing to the developed situation appeared in relationship. Related marriages are especially frequent at the people living in mountains and on islands. During times far from us the Egyptian Pharaohs, aspiring to keep the power, the earths, riches, encouraged related marriages, It the Spanish royal houses differed also. Harm of related marriages was known since times of an extreme antiquity and corresponding interdictions can be found in the Bible, the Koran, the Talmud.
Both nevertheless and today related marriages not a rarity. I and my colleagues within several years had to conduct in forwarding conditions inspection of children in the small settlements removed from large cities. In them very big percent of the related marriages which had the beginning with 1735.г was marked. As a result in these villages the big number of carriers of the same "sick" genes has collected. Related marriage is dangerous that the husband and the wife possess the raised number of identical genes and, hence, the risk of the introduction into marriage of 2 carriers of the same "sick" genes and a birth of sick children is especially high .
Knowledge of elementary data of a heredity are necessary for one reason. These data allow to address in due time for medical aid — in медикогенетическую consultation. Врачконсультант can not only explain the arisen questions, but also to define degree of risk of such marriage, to give the forecast of the future posterity, i.e. To approach to the decision of this difficult and delicate question from scientific positions. It is necessary to mean also, that achievements of modern medicine are that, that in variety of cases the diagnosis can be put till a birth of the child, i.e. In the pre-natal period of its development. Such medical aid has received the name пренатальной diagnostics. On early terms of pregnancy the woman is surveyed by means of ultrasound, at it undertake околоплодные waters and the fruit chromosomal complement is defined. Developmental anomalies of a fruit, chromosomal illnesses can be thus revealed, the sex of a fruit is defined, etc.
It is necessary to mean, that пренатальная diagnostics is especially important for those women which family tree is complicated by hereditary diseases (in the area of mother and the father). It also concerns and those women which pregnancy has come to the end before with a spontaneous abortion, мертворождением or a birth of the child with developmental anomalies. Not smaller value has also age of the woman as it is known, that after 36 years with each next year the risk of a birth of the sick child increases, Пренатальная diagnostics is spent on early terms of pregnancy (11—14 weeks). The doctor informs results of researches to the future parents. In case of detection of a fruit with congenital defects the doctor informs a married couple. The decision on pregnancy interruption is accepted by them independently. Certainly, it is given to them hardly and demands careful considering, numerous councils with experts. But, unfortunately, time for decision-making happens a little as pregnancy interruption can occur only in strictly certain terms.
The young men marrying, the forecast of their future posterity can interest. Especially often such problems arise, when in families of these people there are relatives with какимилибо chronic diseases: mental frustration, a diabetes, illnesses of a skeleton, etc. For the doctor advising them special value is got by data of medical character: who is sick in a family with what this disease when it was found out for the first time etc. communicates. Only the knowledge of the exact diagnosis allows to give well proved answer. At one diseases the risk of a birth of the patient with congenital defects is low and fluctuates within 3—5 %, at others it reaches 25, 50 or 100 %.
Let's assume, that your children who have married, there have passed all these "tests" and you became grandmothers and grandfathers. In a family there was a new desired member of a family. In maternity hospital it has been carefully examined by the doctor, and its state of health did not cause any doubts. However time of alarms and necessity of constant supervision over the newborn has not come to an end. Each parent, and also grandmothers and grandfathers, constantly communicating with the child, always should mark both its achievements, and lacks. Well-known terms when the child should start to smile, watch a toy to learn the relatives, to hold a head, to sit, go, etc. Deviations during mental, emotional and physical development always should cause alarm and requirement for consultation of the pediatrist. Young parents should know, that there are hereditary illnesses of a metabolism. The born child can be outwardly healthy, but lag behind in development. These diseases though meet seldom, but lead to heavy consequences — to occurrence of psychoneurological frustration. In a basis insufficiency or full absence of this or that enzyme therefore there come metabolism infringements lays . To such diseases which have received the name ферментопатии, concerns, for example, фенилкетонурия, At other disease — галактоземии — there comes intolerance of chest milk and there is an infringement of a carbohydrate exchange.
To warn heavy consequences of these frustration, special diagnostic programs — "sifting" programs now are developed. Main principle of these programs — obligatory inspection of all newborns on фенилкетонурию and congenital гипотиреоз (insufficiency of function of a thyroid gland at the child). For this purpose some drops of blood are necessary. At more rare hereditary diseases of a metabolism other so-called program of selective (selective) inspection of children of the first year of a life is used. Young parents should know, in what cases they should address for consultation to the doctor:
Congenital defects of development of those or other bodies (the unusual form of a head, the auricles, the changed form of hands, feet, accrete or superfluous fingers and пр,);
Unusual colour (blackening or turning blue diapers) or smell (mould) of urine at children of the first days or weeks of a life;
The facts of an inexplicable delay of mental and physical development;
Intolerance of milk and dairy products (a diarrhoeia, vomiting, losses in weight);
Intolerance of the products prepared from cereals (a rye, wheat and др)
The attentive relation to the child, the grandson or the grand daughter and the timely reference to the doctor is very important, as at these diseases there are rather effective methods of treatment. Often they are reduced to a medical diet: to cancellation of chest milk and replacement with its special dairy mix, from which the product (dairy sugar, глютен, etc.), to appointment of vitamins В1 В6, With is excluded intolerable by an organism, About, etc.
Experience of dialogue with parents of sick children convinces that many young parents, and also grandmothers and grandfathers have very weak idea about a condition and possibilities of rendering of medical aid to a family having patients with hereditary diseases. From year to year these possibilities increase, and necessary councils can be received in such new medical institutions as marriage and family consultation, медикогенетическая consultation, etc. it is necessary to mean, that now the medicine has the big arsenal of the diversified means for treatment of patients with hereditary infringements of a metabolism, illnesses of eyes, bone system, heart and many other things. It is necessary to remember, that the care of health of the future parents always assumes care of health of their posterity.
The author: Ю. And, Барашнев, the doctor of medical sciences
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