[Organization of medical genetic service in Russia].

Short history of the development of medical genetic service in Russia from the 1960s till now is described. Analysis of many orders of the Ministry of Health of USSR and Russia was performed which shows how separate components of the service were designed and integrated into the efficacious genetic counseling system. All of them were supported by educational programs. The important contribution made by professor Nikolai Bochkov to the creation of genetic service in Russia especially at the early stages is underlined.

[Integrated population genetic and medical genetic study of two raions of the Tver oblast]. / Kompleksnoe populiatsionno- i mediko-geneticheskoe issledovanie naseleniia dvukh raionov Tverskoi oblasti.

An integrated medical genetic an population genetic study has been performed in two raions (administrative districts) of the Tver oblast (region) of Russia: the Udomlya raion located in the zone affected by the Kalininskaya Nuclear Power Plant and the Ostashkov raion, which served as a control district. No significant differences has been found with respect to the genetic parameters studied. The values of these parameters in the populations of the town of Udomlya, the town of Ostashkov, the Udomlya raion, and the Ostashkov raion, respectively, are the following: random inbreeding, 0.00006, 0.00011, 0.000167, and 0.000366; endogamy index, 0.05, 0.43, 0.30, and 0.42; local inbreeding, 0.0003, 0.00045, 0.0009, and 0.0011; the degree of isolation by distance, 0.0003, 0.00045, 0.0009, and 0.0005; sigma, 2098, 1338, 1473, and 1189; the load of autosomal dominant (AD) diseases, 0.71, 0.92, 0.92, and 1.37; the load of autosomal recessive (AR) diseases, 0.68, 0.69, 0.67, and 0.82; and the load of X-linked diseases, 0.18, 0.64, 0.83, and 0.27.

[Hereditary cancer: identification, genetic heterogeneity, medico-genetic consult]. / Nasledstvennyi rak: identifikatsiia, geneticheskaia geterogennost', mediko-geneticheskoe konsul'tirovanie.

The paper deals with a role of inherited factors responsible for the occurrence of malignant tumors. Inherited types of cancer are shown to occur virtually at its sites and averaged 5-15%. Formalized criteria for identifying inherited cancer diseases and their etiological and genetic heterogeneity are presented. A role of genes that genetically predispose to particular forms of cancer is shown, which allows for early (preclinical) diagnosis and prevention of cancer diseases.

[Genetic epidemiological study of populations in three regions of Chuvashia Republic]. / Genetiko-épidemiologicheskoe izuchenie naseleniia trekh raionov Respubliki Chuvashiia.

Comprehensive population genetic and medical genetic studies were performed in three raions (districts) of Chuvashia. The population of these districts is more than 90% Chuvash. About 70% of the families that completed reproduction had two or three children. The proportion of families with four or more children was 18%. The duration of generation was 27.6 years. The differential fertility and differential mortality indices in the Chuvash population were estimated at 0.33 and 0.076, respectively. The total index of differential selection was 0.403, which is typical of modern urbanized populations. Mean values of local inbreeding calculated from Malecot's model of isolation by distance were 0.00124 and 0.00377 for the urban and rural populations, respectively, of the districts studied. The prevalence rates of autosomal dominant (AD), autosomal recessive (AR), and X-linked diseases were found to be 0.47, 0.52, and 0.35 per 1000, respectively, in the urban population and 1.62, 1.14, and 0.31 per 1000, respectively, in the rural population. Significant correlation between the local inbreeding and prevalence rates of AD and AR diseases was found. A total of 43 AD and 43 AR diseases were identified. Some of them were not found in previous studies on other populations.

[Burden of hereditary diseases in residents of the Mari El Republic]. / Gruz nasledstvennykh boleznei u naseleniia respubliki Marii El.

A summary of the medical genetic studies of the Marii El population is presented. A total of 276,900 people, 110,894 and 166,006 urban and rural inhabitants, respectively, were examined. Regarding the ethnic composition, the studied population was mostly Mari (61.96%) and Russian (32.04%). Medical genetic examination revealed 480 subjects from 260 families with autosomal dominant (AD) diseases, 234 subjects from 184 families with autosomal recessive (AR) diseases, and 49 subjects from 41 families with x-linked diseases. Segregation analysis revealed a good agreement between the expected and observed segregation frequencies for families with AR and AD diseases and allowed the frequency of hereditary diseases in the urban and rural, as well as the Russian and Mari, populations, to be estimated. The total frequency of AD diseases in Maris was approximately twice as high as in Russians (1.99 and 0.97%, respectively); substantial differences between district populations were found. The total frequency of AR diseases was also two times higher in Maris than in Russians (1.00 and 0.54%, respectively). The frequencies of AR and AD diseases in different districts were correlated with the levels of random and local inbreeding, population size, and the index of maximum selection.

[Diversity of hereditary pathology in the population of Marii El Republic and its differentiation with respect to gene frequencies for hereditary diseases]. / Raznoobrazie nasledstvennoi patologii u naseleniia respubliki Marii El i ee differentsitsiia po chastotam genov nasledstvennykh boleznei.

The diversity of Mendelian hereditary pathology was studied in Marii El Republic. In total, 276,900 subjects, including 171,151 Maris and 88,714 Russians, living in seven raions (districts) were studied. Fifty-five autosomal dominant disease entities were found, with more than ten diseases having a frequency of 1:50,000 people or higher. In Maris, autosomal recessive hypotrichosis was observed at a relatively high frequency (1:15,337); this disease was not revealed in the Russian population studied earlier. Conversely, no phenylketonuria (PKU) was found in Maris, while it was a relatively common autosomal recessive disease in Russians. Regarding autosomal dominant pathology, 76 disease entities were revealed, with 21 diseases being observed at a frequency of at least 1:50,000. Ten X-linked diseases were found. The numbers of both autosomal recessive and autosomal dominant diseases exhibited a linear relationship with the number of subjects examined. The genetic structure of the Mari population was studied on the basis of data on the genes of recessive diseases. A matrix of Nei's genetic distances was calculated from the frequencies of 45 recessive diseases found in the seven districts studied. The average genetic distance calculated for the 45 loci of autosomal recessive diseases was 0.006175 x 10(-3). Similarly, matrix of genetic distances for five Mari populations was obtained (Medvedevskii and Zvenigovskii raions were not included) based on a total of 32 allelic frequencies for ten polymorphic immune and biochemical loci. The average genetic distance calculated from the ten polymorphic loci was 0.001930, i.e., 2.5 orders of magnitude greater than the average genetic distance for recessive diseases. The matrices of genetic distances for the five Mari populations calculated from the gene frequencies for recessive diseases and for the ten polymorphic systems were largely similar to each other. Thus, the main elements of the genetic structure of the Mari population can be estimated on the basis of gene frequencies for hereditary diseases. In this case, the characteristics of individual populations, which are more or less isolated, and of their interaction are the same as in the case of studying genetic structure with the use of polymorphic biological markers.

PCR detection of Y-specific sequences in patients with Ullrich-Turner syndrome: clinical implications and limitations.

Cytogenetic analysis of patients with Ullrich-Turner syndrome (UTS) may fail to detect low levels of Y chromosome mosaicism or Y-derived marker chromosomes. More sensitive polymerase chain reaction (PCR)-based tests have been developed; however, applicability of these data to prognosis of virilization and gonadoblastoma development has not been investigated adequately. We used a multiplex PCR-based method to detect two Y-specific sequences, SRY and AMGLY. Thirteen patients with UTS without cytogenetically detected Y chromosomes were studied. Y-specific sequences were detected in 5 patients by multiplex PCR. A cryptic translocation involving the Y chromosome was found in one patient with severe virilization of external genitalia and a male phenotype. Y chromosomal mosaicism was detected in peripheral blood and in both gonads of one patient, and only in the left gonad of another patient. Existence of a Y-derived marker was demonstrated in 2 patients, one of whom had no testicular tissue or virilization. Consistent with previous reports, we conclude that PCR is more sensitive than classical cytogenetic analysis and detects patients with Y-specific sequences in blood cells. However, the absence of Y-specific material in blood is not a sufficient reason to reject surgical treatment in case of virilization.

[Medico-genetic study of residents of Marii El republic: burden of hereditary diseases in four regions of the republic]. / Mediko-geneticheskoe izuchenie naseleniia respubliki MariI El: gruz nasledstvennykh boleznei v chetyrekh rainakh respubliki.

A medical genetic study of Orshanskii, Morkinskii, Sovetskii, and Semurskii raions (districts) of the Marii El Republic was performed. The total number of subjects examined was 115,743. Meadow Maris and Russians accounted for the most part of the populations of the districts studied. A total of 147 families with presumably autosomal dominant (AD) pathology and 150 families with presumably autosomal recessive (AR) or X-linked pathology (270 and 169 affected persons, respectively) were revealed. Segregation analysis demonstrated a good agreement between the observed and expected segregation frequencies for both AR and AD diseases, as well as a considerable number of sporadic cases of presumably AD diseases. The incidence of hereditary diseases was estimated separately for different population groups. Significant differences in this incidence were revealed between the urban and rural, as well as between the Russian and Mari populations; the average incidence was 2.33 affected subjects per 1000 people. The incidence of AR diseases was significantly higher in Maris than in Russians (1.34 x 10(-3) and 0.82 x 10(-3), respectively). The populations studied exhibited a significant, high correlation between the incidence of AR diseases and the levels of random and local inbreeding. The incidence of X-linked recessive diseases was approximately the same as in Russian populations studied earlier. Its average value was 0.5 per 1000 men; the incidence in the Mari and Russian populations did not differ significantly. The higher AD incidence in the total population studied and the higher AR incidence in the Meadow Mari population compared to the populations studied earlier are discussed.

[Genetic structure and the load of hereditary diseases in five populations of Arkhangel'skaia region]. / Geneticheskaia struktura i gruz nasledstvennykh boleznei v piati populiatsiiakh Arkhangel'skoi oblasti.

A population and medical genetic investigation was performed in a number of raions in the Arkhangel' skaya oblast. Random inbreeding coefficients were 0.000358 and 0.000361 in the Vinogradovskii and Krasnoborskii raions. Malecot's local inbreeding coefficients were 0.000565 and 0.000472, respectively. The endogamy indices were 0.37 and 0.54, respectively. In the urban population, the loads of autosomal dominant, autosomal recessive, and X-linked pathology were 1.01 and 0.98 per 1000 individuals, and 0.29 per 1000 men; in the rural population, they were 1.22, 1.55, and 1.08, respectively. In the populations studied, the hereditary pathology spectrum is described.

[Monogenic hereditary diseases in Gorno-Mariiskii district of Marii El republic]. / Monogennaia nasledstvennaia patologiia v Gorno-Mariiskogo raione respubliki Marii El.

The population of Gornomariiskii raion, Marii El Republic, primarily made up of mountain Marii, was subjected to medical genetic examination. The size of the entire population is 54853. Estimates of hereditary pathology in urban and rural populations of the raion were obtained. They were 0.68 and 1.11, respectively, for autosomal dominant pathology (AD); 0.55 and 0.81 for autosomal recessive pathology (AR); and 0.45 and 0.20 for X-linked pathology. Twenty-two, 25, and six nosologic forms of autosomal dominant, autosomal recessive, and X-linked diseases were revealed, respectively. We attempted to compare the sample under consideration with previously studied Russian and Finnish populations for rare pathologic recessive genes.

[Translocation 11q;22q: a clinico-cytogenetic study]. / Translokatsii 11q; 22q: kliniko-tsitogeneticheskoe issledovanie.

Seven families with translocations t(11; 22) identified at our Institute and analysis of the literature showed that the imbalance resulted from such translocations is always due to nondisjunction 3:1. Nondisjunction occurs more often in the 1st meiotic division, and is more rare in the second one. Expressed prezygotic selection against spermia with an additional chromosome greatly increases the risk of having an imbalanced child for the women-carriers as compared to men-carriers. The phenotype of the patients with +der(22)t(11; 22) is composed of the features characteristic for trisomy 22q (cleft lip and palate, preauricular papillomas and fistulas, rectal atresia or stenosis) and trisomy 11q (long philtrum with the upper lip hanging over, renal al; asia and hypoplasia). Diaphragmatic hernias are found to be common for the patients with +der(22)t(11; 22).

[Clinical importance of determination of lipid peroxidation of erythrocyte membrane in children with mucoviscidosis]. / Klinicheskoe znachenie opredeleniia perekisnogo okisleniia lipidov membran eritrotsitov pri mukovistsidoze u detei.

The intensity of membranous red blood cell metabolism (lipid peroxidation /LPO/ and malonic dialdehyde /MDA/ metabolism) was examined in children suffering from mucoviscidosis depending on the gravity of the clinical manifestations of the disease. The membranopathological processes accompanied by different disorders of membranous metabolism, depending on the patient's status gravity and the intensity of inflammation in the respiratory organs were revealed. Based on the disagreement between different parameters that characterize LPO of red blood cells and MDA metabolism the conclusion is drawn that in children with mucoviscidosis, the metabolic processes occurring at the level of cellular membranes are not balanced. The data obtained point to the necessity of an individual approach to the use of membranoprotectors in multimodality treatment of children with mucoviscidosis together with the control over the treatment efficacy on the basis of a dynamic follow-up of membranous LPO with the aid of the method employed in the work.

[Clinico-genealogical characteristics of hemophilia A in a large inbred kindred]. / Kliniko-genealogicheskaia kharakteristika gemofilii A v bol'shoi inbrednoi rodoslovnoi.

The results of the clinico-genealogical investigation of patients with mild haemophilia A in a large azerbaijanian highly inbred kindred (446 members in VII generations) are presented. Some peculiarities of the disease segregation are discussed. The prevalence of the haemophilia A in the population examined was estimated as about 1:440.

[Analysis of the patient contingent at a specialized pediatric clinic]. / Analiz kontingenta bol'nykh detskoi spetsializirovannoi kliniki.

Clinico-syndromologic, cytogenetic and biochemical screening embraced 330 patients of a specialized pediatric clinic. Of all cases of diseases 78.8% were either fully or partially accounted for by hereditary factors: 54% chromosome-related syndromes, 5.2% monogenic syndromes, 3.6% nonclassified combinations of developmental anomalies 16% isolated congenital defects of development. Others (21.2%) displayed the organic CNS defects, embryo- and fetopathies due to environmental impacts. The study resulted in diagnosis changes in 6.7% of the cases and identification of 14 hereditary syndromes. The prevalence of hereditary pathology in the morbidity structure of this contingent strongly suggests the necessity of medical genetic consultation in their families.

[Population-demographic and clinico-genetic characteristics of Huntington chorea in one region of Azerbaijan]. / Populiatsionno-demograficheskaia i kliniko-geneticheskaia kharakteristika khorei Gentingtona v odnom iz raionov Azerbaijana.

The data are presented on prevalence and clinical patterns of Huntington disease in Shamkhor region of Azerbaijan, where about 126.8 thousand inhabitants live. Population, demographic and genealogical data show that high prevalence of Huntington disease in that region is determined by the founder effects, reinforced later by extended reproduction of the population. Linkage analysis using the affected sib-pair method failed to reveal a linkage between Huntington's chorea locus and HLA, AB0, MN systems. Significant probability of linkage to Huntington's chorea locus was calculated for Gc marker.