RESUMO
The dynamics of the lethal equivalents in two rural populations of Archangelsk regions during the periods from 1930 to 1953 and from 1954 to 1970 was investigated. The outcomes of 1617 pregnancies for 500 couples were analysed. The coefficient of inbreeding varied fo these couples from 0.001 to 0.08. For computing the genetic load, we followed the the methodology suggested by Morton, Crow and Muller in S. Smith's modification. The importance of comprehensive determination of inbreeding coefficient for reliable estimation of the genetic load was demonstrated. By comparing the two groups, it was shown that the coefficient B diminished approximately twice and the B/A ratio increased in both populations also by the factor of two. It is supposed that the diminishing of the number of lethal equivalents can be explained by a decrease in natural selection pressure. It is also supposed, that the segregational load is more sensitive to the decrease in natural selection pressure.'
Assuntos
Genética Populacional , Consanguinidade , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Gravidez , População Rural , Federação Russa , Seleção GenéticaRESUMO
The population-genetic study of an elementary rural population located in the Urgut district of Samarcand province was carried out. The pedigree for the whole population starting from the founders was evaluated. From 208 marriages presented in the population, 148 (71.2%) were consanguineous. The mean coefficient of inbreeding calculated from the pedigree was 0.028. A new approach to the evaluation of marital assortativity in a rural Uzbek population without tribial differentiation and inherited surnames was proposed. It consists in awarding artificial surnames to the founders of the population. Applying this approach to the population under study gives following values of F-statistics: FIT = 0.031, FIS = 0.01841, FST = 0.01282.
Assuntos
Consanguinidade , Feminino , Masculino , Nomes , Linhagem , População Rural , TadjiquistãoRESUMO
The essential moments of the computer algorithms - a construction of pedigree patterns and determination of inbreeding coefficients - are described. The main attention is given to the field material prossesing for the computer system. The common program is composed to three subprograms: pedigree construction, F estimation and evaluation of information quantity concerning the ancestors. The principal algorithms of the pedigree subprogram is based on computations of a parents computer adress from the proband's code. Such a run is repeated from generation to generation, until the information of ancestors comees to zero. Common ancestors for Wright's inbreeding estimation have been found by sorting out and comparison of husband's and wife's ancestors. The inbreeding coefficient has been formed as the kinship coefficient of parents.
Assuntos
Computadores , Linhagem , Feminino , Humanos , Masculino , MétodosRESUMO
The paper deals with two demographic characteristics of 6 villages in the Archangelsk Region of the RSFSR (river Peosa region) significant from the genetical standpoint. These data were obtained by means of the examination of 843 persons (75,07% of the total number of inhabitants) and of the analysis of complete list of inhabitants permanently living in the villages studied. The proportion of the reproductivity age class was 28.94%, the numbers of men and woman among them being about equal. The average number of children per family in families that have already completed their reproductive period was 3.87, the variance being 4.51 (the data obtained on the basis of examination of over 90 families). The average age of marriage was established to be about 24 years, the duration of each generation being about 32 years. The average index of endogamy per village was observed to be 58.40%, the contribution of the gametes of the preceding generation per village being 72.86%. The migrational influx of gametes from other localities per total of 6 villages was 2.52%. It was shown by the comparison of the character of migrations with mathematical models that the matrix migrational model is the most adequate one.
Assuntos
Genética Médica , Genética Populacional , Características da Família , Humanos , Masculino , Federação RussaRESUMO
Heritability of fertility was determined in populations with natural character of reproduction (Middle Asia Republics) and in populations with family planning (Middle Russia). The material was collected by interviewing the married women of postreproductive age. The heritability of fertility was estimated as a doubled coefficient of correlations between sisters for effective fertility. In populations with natural character of reproduction the heritability was about 50% and it did not differ from O in the populations with family planning. The values of heritability were used in the components of the Crow index analysis. The main contribution into broad-sense heritability of fertility comes from additive component, as shown in an Asia population (Turkmen). The values of heritability of fecundability (86%) and of postpartum sterility (66%) have been calculated for the same population.
Assuntos
Fertilidade , Genética Populacional , Seleção Genética , Ásia Central , Etnicidade , Feminino , Humanos , Infertilidade Feminina/genética , Período Pós-Parto , Gravidez , População Rural , Federação Russa , População UrbanaRESUMO
The index of the total opportunity for selection (the Crow index) and the genetic part of total variance in progeny size was studied in small Turkmenian isolated population "Nochur". The average number of children per family in families that had completed their reproductive period was 6.84, the variance being 12.31. The index of total opportunity for selection was computed by the standard method of J. Crow: Jm = 0.313, Jf = 0.454, Jtot = 0.909. Some correlation coefficients of the progeny size were calculated. The sister-sister correlation coefficient was significantly distinguished from 0 and was equal to +0.22. Thus, the genetic part of total variance of the progeny size is 0.4-0.5. It is essential for understanding of the Jf estimation.
Assuntos
Etnicidade , Fertilidade , Genética Populacional , Adolescente , Criança , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção Genética , TurcomenistãoRESUMO
The possible usefulness of Russian surnames as a quasi-genetic marker in the population study is analysed. Two approaches for the populations of different hierarchical levels are used. The coefficients of correlations between the matrices of genetical (based on gene frequencies in the populations) and quasi-genetical (based on surnames frequencies in the populations) distances were determined. The mean correlation coefficient is 0.315 +/- 0.15. Genetical and quasi-genetical distances and the level of gamete exchange between populations are connected, being reversely dependent. The mean correlation coefficients are: -0.63 +/- 0.13 and -0.23 +/- 0.16. The correlation coefficient for matrices of quasi-genetical and geographical distances was 0.39 +/- 0.08, this being -0.42 +/- 0.08 for matrices of quasi-genetical distance and geometrical mean of population dimensions. It is shown that surnames can replace genetic markers in description of the population genetic structure and in the study of the processes influencing this structure.
Assuntos
Marcadores Genéticos , Genética Populacional , Nomes , Antígenos de Grupos Sanguíneos/genética , Humanos , Federação RussaRESUMO
A method for reconstruction of genetic distances' matrix, based on linear combination of physical distances' matrices among populations and mean sizes of the population matrices is proposed. The analogue of genetic distances' matrix obtained correlates with the matrix at the level 0.59. The reconstruction may be used for the populations of about 2-3 neighbour districts. An index xi is introduced, as a constant describing some big regions. Comparison of reconstructed matrix of genetic distances with some well-known matrices of genetic distances is performed.
Assuntos
Genética Populacional , Modelos Genéticos , Alelos , Humanos , MatemáticaRESUMO
Two kinds of matrices of genetic distances were compared. The first originate from the distribution of surnames frequencies in communities of some districts of Kostroma province. The others were constructed, based on the population size and the physical distances between populations. Essential similarity in results obtained by these two methods was noted. The differences arise, due to the elements of infrastructure in the real populations which are not taken into account using the second method.
Assuntos
Genética Médica , Genética Populacional , Modelos Genéticos , Humanos , Matemática , Federação RussaRESUMO
Data on distribution of various types of hemoglobinopathies in the Krasnodar region are presented. This region was unfavourable, due to malaria in the past. The results obtained allow to conclude that the territory needs more attention as a possible focus of beta-thalassemia in our country.
Assuntos
Hemoglobinopatias/genética , Feminino , Frequência do Gene , Hemoglobinopatias/epidemiologia , Humanos , Masculino , Federação Russa , Talassemia/epidemiologia , Talassemia/genéticaRESUMO
The article comprises the examples of homophenogamic marriages between persons with a rare hereditary dominant character, hand-palm and foot-sole hyperkeratosis, leading to the increase of inbreeding intensity in the population. On the contrary, homophenogamic marriages between persons with vitiligo, a considerably more widespread character, lead to the decrease of the degree of inbreeding in a population, since they take place between partners coming from different districts of the region.
Assuntos
Ceratodermia Palmar e Plantar/genética , Vitiligo/genética , Feminino , Genética Populacional , Humanos , Endogamia , Ceratodermia Palmar e Plantar/epidemiologia , Masculino , Linhagem , Uzbequistão , Vitiligo/epidemiologiaRESUMO
The paper deals with the distribution of genetic markers (systems ABO, MN, Rh (D), Hp, PTC) and a number of demographic (folding of arms, hand clasping, tongue rolling, right- and left-handedness, of the type of ear lobe, of the types of dermatoglyphic patterns) in the inhabitants of 6 villages in the Mezen District of the Archangelsk Region of the RSFSR (river Peosa basin). The data presented in this work were obtained in the course of examination of over 800 persons. Differences in the interpretation of the results of generally adopted methods of statistical analysis of samples from small populations are discussed. Among the systems analysed in one third of all the cases there was a statistically significant deviation from Hardy-Weinberg's ratios. For the MN blood groups and haptoglobins this was caused by the excess of heterozygotes. The test of Hardy--Weinberg's ratios at the level of two-loci phenotypes revealed no statistically significant deviations either in separate villages or in all the villages taken together. The analysis of heterogeneity with respect to markers inherited according to Mendel's law revealed statistically significant differences between villages in all the systems except haptoglobins. A considerable heterogeneity in the distribution of family names, the frequencies of some of them varying from village to village from 0 to 90%. Statistically significant differences between villages were shown for all the anthropogenetic characters except arm folding, hand clasping and right-left-handedness. Considering the uniformity of the environmental pressure in the region examined, the heterogeneity of the population studied is apparently associated with a random genetic differentiation (genetic drift) and, possibly, with the effect of the progenitor.
Assuntos
Antígenos de Grupos Sanguíneos , Genética Médica , Genética Populacional , Dermatoglifia , Feminino , Lateralidade Funcional , Humanos , Masculino , Fenótipo , Federação RussaRESUMO
The paper deals with the distribution of genetic markers (systems ABO, Rh, Hp, PTC) and a number of phenotyping traits (folding of arms, hand clasping, tongue rolling, right- and left-handedness, the type of ear lobe, the types of dermatoglyphics patterns) in the inhabitants of 5 villages in the Pinezhsky district of the Arkhangelsky region of the RSFSR. The data presented in this work were obtained in the course of examination of over 900 persons. Among the systems analysed there was a statistically significant deviation from Hardy-Weinberg's equlibrium. It took place in two the least villages. In one case--for ABO blood groups, in another--for Hp system. There are an interesting fact of the excess of heterozygotes 2-1 and some excess of the group 0. Statistically significant differences between villages were shown for four genetic systems. Data on migrations, distribution of gene frequencies and estimated genetic and phenotype distances between villages of the same village community and between two communities suggest, that each village community can be considered as separate subdivided population. Considering the uniformity of the environmental pressure in the region examined, the heterogeneity of the population studied is apparently associated with a random genetic drift.
Assuntos
Genética Populacional , Antígenos de Grupos Sanguíneos , Dermatoglifia , Orelha Externa , Lateralidade Funcional , Frequência do Gene , Humanos , Fenótipo , Postura , Federação Russa , Língua , MigrantesRESUMO
Computer program "RODAN-1" is used for inbreeding coefficient estimation. The population studied consists of two communities of 5 villages. 385 marriages were computed. The coefficient of inbreeding is 0.00145 for pedigree for rural Russian population (the Arkhangelsk region). The inverse dependence between a village size and corresponding data of inbreeding coefficient is suggested. An attempt was undertaken to estimate the genealogical information value for each pedigree and average information value for a village.
Assuntos
Consanguinidade , Genética Populacional , População Rural , Regiões Árticas , Computadores , Feminino , Humanos , Masculino , Linhagem , Federação RussaRESUMO
The screening for families burdened with multiple cases of non-infectious diseases, the diagnostic of those diseases and the investigation of relations between the population structure and the distribution of hereditary diseases in 4 districts of the Kashkadarja province were carried out. On the basis of the data obtained the load of excessive hereditary diseases was calculated and nosological spectrum was described; it included more than 30 different diseases. The study of spatial distribution of recessive diseases has shown that the load of hereditary diseases may be accounted for the positive assortative matings. The high level of interpopulation migration prevents from the local accumulation of a certain hereditary disease.
Assuntos
Doenças Genéticas Inatas/epidemiologia , Genes Dominantes , Genes Recessivos , Genética Populacional , Humanos , UzbequistãoRESUMO
Medico-genetic characteristics of the Ashkhabad province of Turkemenia are given. 23 nosological forms of hereditary diseases were found. The population load estimated per 1000 of autosomal-recessive (AR) diseases was 0.7, autosomal-dominant (AD) - 0.4, X-linked - 0.5. Inbreeding coefficient for the families with AR pathology was 0.03529, with AD - 0.01172. The study of territorial distribution of hereditary disease detected slightly marked local accumulation of certain forms of hereditary diseases.
Assuntos
Aberrações Cromossômicas/epidemiologia , Doenças Genéticas Inatas/epidemiologia , Transtornos Cromossômicos , Consanguinidade , Feminino , Genes Dominantes , Genes Recessivos , Genética Populacional , Humanos , Masculino , Isolamento Social , Turcomenistão , Cromossomo XRESUMO
The structure of the populations in Korenovsk and Ust-Labinsk districts--sexual, age, family and migrant is described Reproduction is low in these populations. The after-reproduction age class in rural populations prevailed, which affects the ratio of recessive and dominant forms in hereditary pathology of these populations. Family planning in towns accounts for small size of the families and decrease of the role of natural selection. Gametic and endogamy indexes for these populations indicate that intensive migrant processes take place in populations studied, as shown by the level of recessive pathology. The results obtained can be used in the medical-genetic studies for this territory.
PIP: To evaluate the pattern of Mendelian hereditary pathology in Krasnodav Krai, the demographic structure of two populations from the central part of Krasnodav Krai (Korenovsk and Ust'-Labinsk regions) was studied. THe age structure of the rural population was characterized by a predominance of the 47 year-old age group (0.406 compared with 0.262 and 0.332 for 0-18 and 19-46 year old age groups, respectively). The prevalence of an adult population resulted in the prevalence of autosome dominant diseases (0.92/1000, compared with 0.56/1000 for autosome recessive diseases). Family size and pregnancy outcomes were analyzed in 170 women who were past the reproductive age. Relatively small average family size (2.06) was indicative of active family planning regulated primarily by the means of induced abortions (3.69/woman). the length of generation calculated from the data on age-dependent fertility was 29.17 years for men and 19.12 years for women. The index of total selection calculated from the Crow index for pregnancy outcomes was 0.653, which was indicative of a less marked contribution of differential mortality and differential fertility to the intensity of natural selection. The endogamy indices for the urban populations of Korenovsk and Ust'-Labinsk regions were 0.174 and 0.195, respectively, while for the rural population of Ust'-Labinsk region, the endogamy index was 0.364. The gamete index for Korenovsk region was 0.142. The calculated values of gamete and endogamy indices were indicative of intensive migration processes, weak isolation by distance, and minimal inbreeding.
Assuntos
População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Fatores Etários , Serviços de Planejamento Familiar/estatística & dados numéricos , Feminino , Genética Populacional , Humanos , Masculino , Gravidez , Resultado da Gravidez/epidemiologia , Federação Russa , MigrantesRESUMO
Medical-genetic study was carried out in the population of Samarkand province (the population size about 150 000). Hereditary pathology was ascertained among families with two or more affected members with chronic diseases. 110 families with 210 patients were registered. The most frequent were autosomal-recessive disorders (42 nozological forms). 15 nozological forms are probably "new" conditions in this province, because they were absent in our previous medical-genetic study of this province. A tendency to local accumulation of families with the same disorder in small populations was observed. The load of autosomal-recessive disorders comprised 2.2 X 10(-3) affected, that of autosomal-dominant disorders being 0.51 X 10(-3) and of X-linked disorders being 0.25 X 10(-3) males. The importance of assortative maitings in manifestation of rare autosomal-recessive genes in Uzbek population is discussed.
Assuntos
Doenças Genéticas Inatas/epidemiologia , Genética Populacional , Feminino , Frequência do Gene , Genes Recessivos , Ligação Genética , Humanos , Masculino , Uzbequistão , Cromossomo XRESUMO
Medical-genetic study was carried out in the population of Khorezm province (population size above 200 000 persons). Hereditary pathology was ascertained among families having two or more members affected with chronic non-infectious diseases. 155 families with 348 members affected with hereditary diseases were registered. The most frequent were autosomal recessive diseases (55 nosological forms in 104 families with 271 affected), then followed the autosomal dominant conditions (10 nosological forms in 21 families with 53 affected). The less frequent was X-linked recessive pathology (6 forms in 12 families with 20 affected). The main part of cases of autosomal recessive pathology were found in separate families and were not observed during previous medical-genetic studies in Uzbekistan. Three autosomal recessive conditions are probably new forms of hereditary pathology. The important role of assortative matings in manifestation of rare autosomal recessive genes in Uzbek population is discussed.
Assuntos
Doenças Genéticas Inatas/genética , Variação Genética , Consanguinidade , Feminino , Genes Recessivos , Doenças Genéticas Inatas/epidemiologia , Ligação Genética , Humanos , Masculino , Uzbequistão , Cromossomo XRESUMO
The load of hereditary diseases was estimated on the basis of data obtained during medical-genetic study of the population of four districts of Khorezm province. The load of autosomal recessive disorders comprised 2-3 X 10(-3) affected, that of autosomal dominant disorders - 0.4-0.5 X 10(-3) and that of X-linked disorders - 0.2-0.4 X 10(-3) males. The main part of patients with autosomal recessive disorders belonged to separate families randomly spread over the populations. A trend for local accumulation of families with the same disorder was observed in small populations. It was shown that overall frequency of autosomal recessive genes per individual increased with the increase in the population size.