GENETICS OF THE PERSON

From Big Medical Encyclopedia

GENETICS OF THE PERSON (the Greek genetikos relating to an origin) — the section of genetics studying the phenomena of heredity and variability at the person. Methods and actual data of G. of h are used in separate sections of anthropology. The term «genetics of the person» is not identical to the term «anthropogenetics». The anthropogenetics studies genetic aspects of anthropogenesis: inheritance normal antropol, signs (a blood group, the sizes of a skull, a dermatoglyphics, color of eyes and hair etc.), genetic processes in populations (selection, drift of genes, isolation). Of h it is connected with all aspects of studying of a human body.

In G. h apply the following methods: genealogical method (see), twin method (see), population and statistical (see. Population genetics ), cytogenetic (see. Cytogenetics ), geneticists of somatic cells (see), modeling. Each of these methods is based on studying biochemical, immunol., morfol., fiziol., wedge, signs. The more discrete the sign is chosen, the its hereditary character is established more precisely.

The genetic analysis of the person is complicated by duration of the reproductive period of the person, small number of posterity, impossibility of experimental marriages and standardization of the environment, a large number of chromosomes. At the same time a phenotype of the person (see. Genotype ) it is in detail studied with biochemical, morfol., fiziol, points of view. It promotes studying of his heredity.

Value G. of h for medicine consists that it is the cornerstone of the big section of medicine — medical genetics (see). The doctrine about hereditary pathology of the person generally is based on the patterns opened by G. for h. In all sections of medicine the doctor faces hereditary pathology. It is known apprx. 2000 forms of hereditary diseases. G.'s progress of h refracts in applied medicine in the form of development of new diagnostic methods, treatment and prevention of hereditary diseases.

Modern G.'s foundation for h began to be laid only at the end of 19 century. However in 1750 Mopertyui (R. of L. M of Maupertuis) and in 1814 J. Adams described some features of inheritance of separate signs. In 1875 Mr. F. Galton offered a twin method for differentiation of a role of heredity and Wednesday in development of signs in the person. It and its school, besides, it was much made in the field of studying of inheritance of quantitative characters.

In 1908 A. E. Garrod for the first time described hereditary diseases of a metabolism and connected their pathogeny with the genetic block in chains of metabolic processes, having actually laid thereby the foundation of modern biochemical genetics (see). Same year Hardy (G. N of Hardy) and W. Weinberg independently from each other formulated the fundamental law of population genetics concerning frequencies of genes in populations. W. Weinberg offered also a method for definition of a share of monozygotic twins and a method of elimination of distortions at identification of a share of sibs (the children of the same parents coming from different zygotes) with a recessive ancestral feature.

In 20 — the 30th 20 century of a research on G. of h are intensified. The analysis already not only separate families, but also big groups of the population in different regions of the country is carried out. As a result of specification of diagnosis of a zigotnost the twin method began to be applied especially widely. Researches of mutational process at the person began. Methods of indirect assessment of frequency of emergence of mutations were offered [V. P. Efroimson, Haldane (J. Century of S. Haldane)].

In 1932 — 1937 in the USSR functioned Medicogenetic in-t, created at the initiative of S.G. Levitte, studying of cytogenetics of the person, twins, diseases with hereditary predisposition was carried out to Krom. Unlike foreign genetics, in a cut the main attention was paid to rather rare and easily diagnosed diseases, studying of interaction of heredity and Wednesday in development of diseases was the main objective Medicogenetic in-that. S. N. Davidenkov's works on polymorphism of hereditary diseases of a nervous system performed in the 30th were of great importance. They were fundamental not only for studying of hereditary pathology of a nervous system, but also for all a wedge, geneticists.

The eugenical movement which arose at the end of 19 century and developed in the 20th 20 century only compromised G. h as science. From time to time the eugenical ideas turned into very dangerous weapon. In Germany, e.g., after arrival of fascism to the power the eugenical ideas were adopted as biol, justification of «fight for purity of race» («racial hygiene»). Similar concepts appear in foreign literature still. However most of progressive geneticists resolutely rejects social Darwinism (see. Darwinism ) and expanded programmes of positive eugenics (see).

In the 50th 20 century the new wave of researches on G. of h in connection with progress of the general and radiogenetics was noted. So, as a result of basic researches of abnormal hemoglobin at drepanocytic anemia the determining role of a gene in synthesis of protein was found out. Thanks to progress biochemical and molecular genetics (see) broad studying hereditary biochemical, polymorphism of the person and diseases of a metabolism began. In 1956 exact chromosome number was determined, and in 1959 — chromosomal diseases of the person are open. Thus, on a new basis problems of cytogenetics of the person began to be developed.

It is possible to allocate the general, biochemical, immunogenetic, cytogenetic, clinical, population, etc. sections G. of h.

General G. of h. studies linkage groups (all genes of one chromosome), localization of genes in chromosomes, correlation of ancestral features, a thin structure of genes, inheritance of normal signs, mutational process, a ratio of heredity and Wednesday in development of normal signs. Great success in studying of linkage groups is achieved. 24 linkage groups are already known, many of which are marked by several genes. Of h has several methods for opening of linkage groups. Progress in studying of mendeliruyushchy factors at the person is undoubted. By 1975 more than 2300 Mendelian characters behaving in the genetic relation according to Mendel's laws are described already (see. Mendel laws ). Great success is achieved in the field of studying of mutational process at the person (see. Mutation ). Its quantitative patterns are described for gene, chromosomal and genomic level.

Biochemical, genetics studies biochemical, methods mendeliruyushchy markers, traces a way from a gene to a sign. Among numerous biochemical, methods especially important role h played the methods of an electrophoresis and a chromatography allowing to find abnormal proteins in G.'s development. One of large achievements of G. of h — establishment of hereditary polymorphism. E.g., more than 100 options glyukozo-6-fosfatdegidrogenazy, 18 of types of transferrins etc. are described already apprx. 200 options of hemoglobin (G. A. Annenkov, E. S. Dementieva). Great success is achieved also in the field of molecular mechanisms of hereditary diseases. It is already known per-the 4th eternal defect at the level of enzyme more than at 130 hereditary diseases. By means of biochemical, geneticists are developed express diagnostic methods of hereditary diseases, including methods of prenatal diagnosis. At all forms of hereditary diseases found so far it is about mutations of structural genes. Existence of the diseases caused by mutations of regulatory genes is not proved.

Immunogenetics (see) it was allocated in the independent section in connection with a large number already established genetically determined immunol, signs. First of all it is antigens of erythrocytes (their more than 50 are known now), antigens of leukocytes, groups of serum proteins. Immunogenetic patterns are used already in a wedge, practice: hemotransfusion, organ transplantation and fabrics, diagnosis of immunodeficiency, etc. questions. Along with the mutations defining distinctions in an antigenic structure of an organism without patol, effect, many hereditary immunodeficiency are opened.

Cytogenetics of the person studies material carriers of heredity — chromosomes (see).

In somatic and formative cells apply modern methods to a research of chromosomes light and a submicroscopy. More and more wide value gets elektronnomikroskopichesky studying of a structure of chromosomes. However the main characteristics of chromosomal complement and data on a thin structure of chromosomes are obtained by means of light microscopy. In cytogenetics of the person various methods of coloring of chromosomes, an autoradiography, fluorescence, hybridization nucleinic to - t are widely applied. All this allowed to identify completely chromosomes of the person, to obtain data on their linear differentiation on length. Especially important success of cytogenetics of the person is discovery of chromosomal diseases and further development of this problem.

Subject wedge, geneticists hereditary diseases, and also diseases with hereditary predisposition are. Hereditary pathology is described for all bodies and systems. It occupies the increasing specific weight in the general incidence of the person. The part a wedge, geneticists studying hereditarily caused patol, reactions to pharmaceuticals, is called pharmacogenetics (see). The main achievement the wedge, geneticists of the last years is discovery of the principle of heterogeneity of hereditary diseases. It led to opening of a large number of new hereditary diseases, gave the chance to understand the principles of their diagnosis and treatment. An immediate task is studying of gene interaction, and also a genotype and Wednesday in development of specific forms of diseases. Along with opening separate patol, hereditary factors searches of systems of the genes contributing to development of diseases are conducted. Eurysynusic diseases are first of all diseases with hereditary predisposition. Aspects a wedge, geneticists are inseparable from anthropogenetics: with the help patol, mutations inheritance of normal signs is analyzed.

Population G. of h. investigates genetic patterns in groups of the population — populations. First of all the following problems are studied: determination of frequencies of genes, value of drift of genes and selection in human populations, process of emergence and preservation of mutations, genetic aspects of a rasoobrazovaniye, origins of the balanced polymorphism, etc. One of important problems of population G. of h — «inventory» of a gene pool of mankind. This area is called a genografiya, her ancestor is A.S. Serebrovsky. Progress in population G.'s area of h allowed to pass to the analysis of evolution of systems of genes, to searches of systems of the genes having this or that adaptive value. Forecasting of future shifts in hereditary human nature is connected with interpretation of ways of evolution. The greatest number of researches about mechanisms of preservation of genetic structure of populations is executed in isolates. As it appeared, these mechanisms very difficult, but at the same time exact and reliable. Use of electronic computers is of great importance for development of problems of population genetics.

Mathematical genetics — G.'s branch of h studying by means of mathematical methods genetic processes, especially at the population level. Progress of mathematical genetics is promoted by accurate statement of tasks from geneticists.

G.'s methodology of h is based on recognition in development of the person of dialectic unity of biological and social factors, proceeding from difficult interaction, but not from the simple sum. As show modern data, for social progress is not present any ©граничений from heredity of the person. On all globe is not present and there were no two identical people on the hereditary qualities. Biologically races, nationalities, groups of people differ, but from the point of view of G. of h any race, a nationality has no advantages over others. Biol. distinction does not mean inequality. In 1939 on the II International genetic congress the resolution containing the requirement to give to all people equal and full opportunities for development irrespective of race, the nation, skin color was adopted.

H rejects an opportunity and need of eugenical interventions in heredity of the person for the purpose of improvement of its nature. Recommendations at medicogenetic consultation for the forecast of posterity or marriage shall proceed from recognition of the right of the solution of a question advised, but not the doctor. The laws on sterilization existing in some countries do not find support from geneticists. Actually these laws are applied in some states of the USA and in Denmark in very limited scales.

In respect of protection of heredity of the person essential value protection has it from mutagen factors which quantity grows in the habitat of the person with technical progress.

Researches on G. of h in the USSR are conducted in laboratories and at departments of both a medical, and biological profile. The relevant departments and large laboratories are available in Ying-those medical geneticists of the USSR Academy of Medical Sciences, at department and in Ying-those anthropology of MSU, in Ying-those ethnographies of Academy of Sciences of the USSR.

Researches on G. of h are widely developed in many countries. In Germany, Denmark, Italy, Sweden, Great Britain, France, the USA there are many large departments of G. of h at the high fur boots called sometimes by institutes according to G. h.

At Academy of Sciences of the USSR is available All-Union about-in geneticists and selectors of N. I. Vavilov (VOGIS), a cut has section according to G. of h. In republican about - Vakh and regional departments of VOGIS sections according to G. of h and medical genetics function.

Ob-va according to G. h are organized in several countries: American about-in on genetics of the person (for the USA and Canada), European about-in on genetics of the person, Japanese about-in on genetics of the person.

Scientific materials according to G. of h in the USSR are printed by hl. obr. in the Genetika magazine and in some other biol, and medical magazines. Abroad according to h magazines are issued: Am. J. Human Genetics (USA), Annals of Human Genetics (Great Britain), Human Biology (USA), Humangenetik (Germany), Human Heredity (Switzerland), Japan Journal Human Genetics (Japan), Journal de genetique humaine (Switzerland), year-book Advances in Human Genetics (Great Britain). Besides, articles according to G. of h are published in medicogenetic magazines: Annales de genetique (France), Acta geneticae medicae et gemellologiae (Italy), Journal of Medical Genetics (Great Britain), Clinical Genetics (Denmark), year-book of Progress in Medical Genetics (USA).

The international congresses according to G. h are carried out once in 4 years. The last (V) congress was to Mexico City in 1976 Besides, G. h is presented on the International genetic congress (1 time in 5 years).

See also Genetics .


Bibliography: Davidenkovs. H. Hereditary diseases of a nervous system, M., 1932; David enkovaye.f. and L and ER of m and N I. S. Klinicheskaya of the geneticist, L., 1975, bibliogr.; Lobashev M. E. Genetics, L., 1967; Makkyyusik V. Genetics of the person, the lane with English, M., 1967; it, Ancestral features of the person, the lane with English, M., 1976, bibliogr.; Nil Dzh. Century ishell At. D. Heredity of the person, the lane with English, M., 1958; Physiological genetics, under the editorship of M. E. Lobashev and S. G. Inga-Vechtomov, L., 1976, bibliogr.; Harris G. Fundamentals of biochemical genetics of the person, the lane with English, M., 1973, bibliogr.; Stern K. Fundamentals of genetics of the person, the lane with English, M., 1965; Efroimson V. P. To an isto-iya of studying of genetics of the person in the USSR, an enetika, No. 10, page 114, 1967; about N e, Introduction to medical genetics, M., 1968; Cavalli-Sferza L. L. a. Bodmer W. F. The genetics of human populations, San Francisco, 1971; Levitan M. Montagu A. Textbook of human genetics, N. Y., 1971; Methodology in human genetics, ed. by W. J. Burdette, San Francisco, 1962.

H. P. Bochkov.

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