Variability of the 3'APOB minisatellite locus in Eastern Slavonic populations

OBJECTIVE: To describe and compare the 3' apolipoprotein (Apo) B minisatellite allele frequency distributions of Eastern Slavonic populations and their Uralic, Altaic, and Caucasian speaking neighbors. METHODS: Healthy individuals of 10 populations among Russians, Byelorussians, Komis and Bashkirs were studied for variable number tandem repeats (VNTRs) in the 3'ApoB minisatellite region. Data were analyzed with other results reported for this polymorphism in eastern Europeans and Siberians. RESULTS: Allele frequency spectra in Eastern Slavonic, Northern Caucasian and Finno-Ugric speaking populations are bimodal with the main peak in alleles 34-36 and a secondary mode around allele 48, whereas Altaic speaking populations have a unimodal allele frequency distribution with a peak of around 34-36 VNTRs. Population relationships were revealed using both multidimensional scaling analysis (based on Nei's genetic distance estimate) and testing for genetic heterogeneity. Eastern Slavonic populations (Russians, Ukrainians, Byelorussians) were most closely related to each other and formed a separate tight clusterwhen plotted. Testing for genetic heterogeneity among the Eastern Slavonic ethnic groups revealed maximum diversity among Byelorussians, followed by Russians, then Ukrainians.The 3'ApoB minisatellite variability reveals little heterogeneityamong the Eastern Slavonic ethnic groups, whereas there wassignificant heterogeneity for Northern Caucasian and Altaic speakers. CONCLUSION: For this 3'ApoB polymorphism the Eastern Slavonic populations, despite their wide geographical distribution, appear to be much more homogenous than other ethnic groups of the region. Multidimensional scaling analysis of these data allowed for differentiation between individual populations from an ethnic group even if there is little heterogeneity.     

Haptoglobin types among the population of western Kazakhstan and their relation to humoral factors of body resistance

Among 803 healthy persons examined, 20.4% of Russians and 18.1% of Kazakhs had Hp 1-1 phenotype, 50.0 and 49.3%, respectively, had Hp 2-1 and 29.6 and 32.6% had Hp 2-2 phenotype. The frequency of Hp1 and Hp2 genes is 0.455 and 0.429, 0.545 and 0.571 (p less than 0.05) for Russians and Kazakhs, respectively. The correlation is established between the haptoglobin type and the level of haemolysins. For example, the latter is greater in number in the organisms of persons possessing the Hp2 gene, especially, when in homozygotic state.     

Analysis of the DRD4 gene polymorphism in populations of Russia and neighboring countries

Allele and genotype frequencies of the VNTR polymorphism in the third exon of human DRD4 gene were determined in 544 individuals living in Russia (Russians, Bashkirs, Tatars, and Mordovians) and in the neighboring countries (Kazakhs and Ukrainians). The data obtained were compared with the allele frequency distribution patterns reported for the populations of Eurasia. Similarly to other Eurasian populations, in our population samples R4 allele was prevalent (64 to 87%). The frequency of this allele in the populations of Western Europe constitute 61 to 71%, while in the populations of Asia it varies from 74 to 96%. In this respect, the populations studied occupied the intermediate position. In the samples examined the R7 allele frequency decreased from 7% in Ukrainians to 1% in Bashkirs, while in Kazakhs and Mordovians the allele was absent. This finding was consistent with the R7 allele distribution pattern in the populations of Eurasia, characterized by higher frequency in the West and lower frequency or absence of the allele in the East. In the group of 22 Eurasian populations, the R7 allele frequency negatively correlated with the frequency of the R4 allele (r = -0.86 at P < 0.001). Unlike the R4 and R7 alleles, the frequency of which changed in the eastward direction, the R2 allele frequency distribution displayed slightly expressed latitudinal increase southwards. The DRD4 genotype distribution deviated from the equilibrium in most of the samples examined. In some samples, statistically significant increase of the R2/R2 homozygotes frequency was demonstrated. One of the possible explanations of this phenomenon is assortative mating with respect to phenotypic (behavioral) allele manifestation. The data obtained can serve as the basis for the investigation of the possible role of the DRD4 alleles as the risk factors for the development of alcoholism and other types of addictions.     

Frequency of CHEK2 gene mutations in breast cancer patients from Republic of Bashkortostan

A number of studies demonstrated that mutations in the CHEK2 gene can increase the risk of oncologic diseases, including breast cancer and that the mutational distribution s depends on the genetic structure of populations. In our study we compared the prevalence of c.1100delC, c.444+1G>A, del5395, p.I157T, and p.R145W CHEK2 mutations in 977 breast cancer patients (Russians, Tatars, Bashkirs, Ukrainians, and individual representatives of other ethnic groups) and in women without any oncologic pathology (n = 1069) from the Republic of Bashkortostan. We found CHEK2 del5395 mutation with a frequency of 1.23% (12/977) in breast-cancer patients, whereas in the control group it frequency was 0.09% (1/1069) (OR: 13.28, CI 95%: 1.72–102.33, p = 0.003). Frequencies of c.1100delC and c.444+1G>A mutations in patients and controls were 0.4%, 0.4% (4/977) and 0.09% (1/1069), 0.2% (2/1069), respectively. The p.I157T substitution in CHEK2 gene was the most widespread variant in two studied cohorts (approximately 5%); however, differences in the frequencies between cases and controls did not reach statistical significance. Truncating mutations were mainly found in women of Slavic origin. All three mutations were found in Russians and Ukrainians. CHEK2 mutations c.1100delC and c.444+1G>A were not found in Bashkirs and Tatars; however, the CHEK2 del5395 deletion was present in Tatars.     

Uptake and effect of praziquantel and the major human oxidative metabolite, 4-hydroxypraziquantel, by Schistosoma japonicum

After exposure to praziquantel in vitro at a concentration of 1 microgram/ml for 0.5-2 hr, amounts of praziquantel in Schistosoma japonicum varied from 2.1 +/- 1.2 to 3.7 +/- 1.6 ng/male worm and 1.3 +/- 1.2 to 2.2 +/- 1.5 ng/female worm during the time studied. At 30 micrograms/ml, praziquantel amounts were 11-33-fold higher. However, within 2 hr after removal from a medium containing 30 micrograms/ml praziquantel, 95% of the drug was released from the parasites. When S. japonicum worm pairs were incubated in vitro with 1, 10, and 30 micrograms/ml of 4-hydroxypraziquantel, the major human oxidative metabolite of praziquantel, 0.2 +/- 0.2, 3.8 +/- 1.3, and 7.4 +/- 1.3 ng/worm pair, respectively, were found after a 2-hr incubation. 15-30-fold lower than corresponding worm pair amounts of praziquantel. In vivo, when 4- or 5-wk S. japonicum-infected mice were treated orally with praziquantel (300 mg/kg), peak concentrations of praziquantel in plasma determined by high pressure liquid chromatography were 14.7 +/- 1.5 micrograms/ml (4-wk infection) and 16.7 +/- 2.8 micrograms/ml (5-wk infection) 15 min after treatment. Corresponding in vivo worm praziquantel amounts were 1.8 +/- 0.4 ng/male worm and 2.4 +/- 1.1 ng/female worm, respectively, in the 4-wk infection and 4.6 +/- 1.6 ng/male worm and 5.6 +/- 1.2 ng/female worm in the 5-wk infection. Peak plasma concentrations of 4-hydroxypraziquantel were similar but corresponding in vivo worm amounts were 1-20-fold lower, depending on the time after drug administration.(ABSTRACT TRUNCATED AT 250 WORDS)     

Genetic demographic data of Ukrainian urban populations in the 1990s: ethno-geographic characteristics of migrants in the Donetsk region

Analysis of data on the birthplaces and ethnicity of persons who contracted marriages in the city of Donetsk in 1960, 1985, and 1992 demonstrated that the proportions of Russians and Ukrainians (the dominant ethnic groups among Donetsk residents) in the migration flow increased. The trend towards formation of ethnically disperse groups from the city residents became stronger. The index of isolation by distance (parameter b of Malecot's model) was 0.00103, 0.00071, and 0.00083 in 1960, 1985, and 1992, respectively. The proportions of long-range and short-range migrants increased by 1.2 times and decreased by 2.3 times, respectively, during the period studied. The locality size of the Donetsk population was 50, 62, and 53 km in 1960, 1985, and 1992, respectively. The highest isolation by distance was observed in Jews and Greeks and the lowest one, in Russians.     

Analysis of the DRD4 Gene Polymorphism in Populations of Russia and Neighboring Countries

Allele and genotype frequencies of the VNTR polymorphism in the third exon of humanDRD4 gene were determined in 544 individuals living in Russia (Russians, Bashkirs, Tatars, and Mordovians) and in the neighboring countries (Kazakhs and Ukrainians). The data obtained were compared with the allele frequency distribution patterns reported for the populations of Eurasia. Similarly to other Eurasian populations, in our population samples R4 allele was prevalent (64 to 87%). The frequency of this allele in the populations of Western Europe constitute 61 to 71%, while in the populations of Asia it varies from 74 to 96%. In this respect, the populations studied occupied the intermediate position. In the samples examined the R7 allele frequency decreased from 7% in Ukrainians to 1% in Bashkirs, while in Kazakhs and Mordovians the allele was absent. This finding was consistent with theR7 allele distribution pattern in the populations of Eurasia, characterized by higher frequency in the West and lower frequency or absence of the allele in the East. In the group of 22 Eurasian populations, the R7 allele frequency negatively correlated with the frequency of the R4 allele (r = -0.86 at P < 0.001). Unlike the R4 and R7 alleles, the frequency of which changed in the eastward direction, the R2 allele frequency distribution displayed slightly expressed latitudinal increase southwards. The DRD4 genotype distribution deviated from the equilibrium in most of the samples examined. In some samples, statistically significant increase of the R2/R2homozygotes frequency was demonstrated. One of the possible explanations of this phenomenon is assortative mating with respect to phenotypic (behavioral) allele manifestation. The data obtained can serve as the basis for the investigation of the possible role of the DRD4 alleles as the risk factors for the development of alcoholism and other types of addictions.     

Genetic Demography of Ukrainian Urban Populations in the 1990s: Ethnic Geographic Characteristics of Migration in the Donetsk Population

Analysis of data on the birthplaces and ethnicity of persons who contracted marriages in the city of Donetsk in 1960, 1985, and 1992 demonstrated that the proportions of Russians and Ukrainians (the dominant ethnic groups among Donetsk residents) in the migration flow increased. The trend towards formation of ethnically disperse groups from the city residents became stronger. The index of isolation by distance (parameter b of Malecot's model) was 0.00103, 0.00071, and 0.00083 in 1960, 1985, and 1992, respectively. The proportions of long-range and short-range migrants increased by 1.2 times and decreased by 2.3 times, respectively, during the period studied. The locality size of the Donetsk population was 50, 62, and 53 km in 1960, 1985, and 1992, respectively. The highest isolation by distance was observed in Jews and Greeks and the lowest one, in Russians.     

Distribution of the HIV-1 resistance-conferring alleles (CCR5delta32, CCR2-64I, and SDF1 3'A) in Russian, Ukrainian, and Belarusian populations

The frequencies of three alleles, CCR5delta32, CCR2-64I, and SDF1 3'A, known to decrease the risk of AIDS onset and the rate of the disease progression in HIV-infected individuals were determined in three native population samples from Russia, Ukraine, and Belarus. The frequencies of the alleles were 0.15, 0.12, 0.21; 0.12, 0.07, 0.20; and 0.12, 0.08, 0.26 for Russians, Ukrainians, and Belarussians, respectively. The proportion of the individuals without any of three protective alleles among Russians, Ukrainians, and Belarussians constituted 49, 65, and 61%, respectively. The genotype frequencies for the three loci studied were in Hardy-Weinberg equilibrium. Based on the three-locus genotype frequencies, the hazard ratios (relative hazards, RH) of AIDS onset in HIV-infected individuals in each sample were calculated as ranging from 0.79 to 0.88. In the samples of Eastern Slavs analyzed the estimated frequencies of the AIDS-protective alleles tested, as well as the frequencies of the corresponding genotypes and the relative hazards of AIDS onset were within the range of these parameters for the other European populations. The data on the allele frequencies and the relative hazard values in Russians, Ukrainians and Belarussians can be used as the predictors of AIDS onset and progression rate in HIV-1-infected individuals from the populations studied.     

Distribution of sialic acid between sialoglycoproteins and other membrane components of different erythrocyte phenotypes.

The sialic acid content of erythrocytes of three different AB0 blood groups have been studied. The sialic acid contents of erythrocyte membranes containing 300 mg protein were determined and compared. Groups 0 (Rhesus negative), AB (both Rhesus negative and positive), and B (Rhesus negative) blood differed significantly (p less than 0.05) in total sialic acid content and in the distribution of sialic acid between sialoglycoproteins and other membrane components. Membrane materials containing 300 mg total protein showed sialic acid contents of 52.73 +/- 2.2 mumol sialic acid for group 0 (Rhesus negative) 34.77 +/- 1.16 mumol for group AB (Rh negative), 32.88 +/- 1.52 mumol for AB (Rh positive) and 21.23 +/- 0.84 mumol for B (Rh negative). In group 0 (Rh. neg.) membranes 39.4 +/- 1.4% of the total sialic acid was associated with the sialoglycoproteins. The percentage of sialic acids associated with sialoglycoproteins in other erythrocyte membranes were 77.7 +/- 1.3% for group B, and 55.6 +/- 1.0% and 56.4 +/- 1.8% for group AB (Rh. negative) and (Rh. positive) respectively. The changes appear to be independent of the Rhesus grouping but dependent on the AB0 grouping since membranes of the two Rhesus types of group AB had identical total sialic acid and sialoglycoproteins sialic acids. The sialic acid densities in sialoglycoproteins also differed from one erythrocyte type to another. Group 0 (Rh. negative) membrane sialoglycoproteins had sialic acid density of 140.5 +/- 3.1 nmol/mg compared to 71.7 +/- 1.2 nmol/mg for group B and 128.1 +/- 2.2 and 124.5 +/- 4.0 nmol/mg for group AB Rhesus negative and Rhesus positive respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Polymorphism of DNA repair genes (XRCC1, XRCC3, XPC, XPD, XPA) in ethnic groups from Republic of Bashkortostan

Genotype and allele-frequency distributions of the excision and homologous recombination of DNA repair genes XRCC1 (rs25487 and rs25489), XRCC3 (rs861539), XPC (rs2228001), XPD (rs13181), XPA (rs1800975) were examined in three ethnic groups from the Republic of Bashkortostan (Russia), Russians, Tatars, and Bashkirs. The data obtained were compared to those for other ethnic groups from Russia and worldwide. Statistically significant differences in the allele-frequency distribution of the XPA gene polymorphic locus rs1800975 (p = 0.03) between the samples of Russians and Tatars were demonstrated. Russians and Bashkirs differed in the allele-frequency distribution of the rs861539 polymorphic locus of the XRCC3 gene (p < 0.0001), and Tatars and Bashkirs, at the rs861539 locus of the XRCC3 gene (p < 0.0001). In Russians and Tatars from the Republic of Bashkortostan, allele frequencies at the DNA repair gene polymorphic loci examined were consistent with those in the population of Northern and Western Europe, while polymorphic allele-frequency distributions in Bashkirs was similar to that observed in the ethnic group of Gujarati Indians.     

Dynamic of marriage structure in three cities of Ukraine from 1960 to 1992

Marriage structure was studied in the city of Kiev and in two cities of the Sumy oblast, Shostka and Trostyanets. Ethnic affiliations and birthplaces of persons contracting marriage were analyzed as the main characteristics of population genetic diversity. The ethnic composition of persons contracting marriage and the proportions of mono- and interethnic marriages remained almost unchanged during one generation. The majority of the persons contracting marriage were Ukrainians (66-91%); among other ethnic groups, only Russians considerably contributed to ethnic diversity (up to 26%). During the period studied, coefficients of marital migration substantially decreased in Kiev (from 0.66-0.82 to 0.34) and Shostka (from 0.72 to 0.52) and changed only insignificantly in Trostyanets. Outbreeding was estimated based on the migration parameters, exogamy level, and marital migration distances. The outbreeding level in the Shostka population (100,000 people) was comparable with that for the considerably larger Kiev population (two million people); however, it was significantly higher than that for the Trostyanets population, the size of which was close to the size of the Shostka population. It is supposed that "migration stress" may unfavorably affect the adaptive genetic structure of the Shostka population.     

Polymorphism of Mitochondrial DNA in Population of Siberian Tatars from Barabinsk Forest Steppe

The analysis of mtDNA polymorphism was carried out in the population of Siberian Tatars from the Barabinsk forest steppe living on the territory of Novosibirsk oblast (N = 199). As a result of the analysis of HVS I and HVS II nucleotide sequence, 101 haplotypes that refer to 22 mtDNA haplogroups were detected. The population of Baraba Tatars is represented by both East Eurasian (38.7%) and West Eurasian mtDNA lines (61.3%). H, T, U5, and J haplogroups prevail among West Eurasian haplogroups; C, D, G, M, and A haplogroups prevail among East Eurasian ones. According to the index of genetic diversity, Tatars from the Barabinsk forest steppe (0.9141) are the closest to Kazakhs (0.9108), Bashkirs (0.9165), and Tobol-Irtysh Tatars (0.9104). The greatest statistically significant interpopulation differences (F_ST) were detected between all studied samples; the smallest interpopulation differences were detected between all Tatar samples, as well as between Tatars and Komi, Mansi, Udmurts, Kazakhs, Chuvashes, and Bashkirs. The haplogroup H is the most common in populations that we studied. In the present study, was registered the haplotype 16126–16294 with the frequency of 4% (T cluster) previously found only in Caucasians. High frequency of haplogroups U4, U5, and H in the gene pool of Baraba Tatars brings them together not only with Samoyeds but also with Finno-Ugric populations. The highest intrapopulation genetic diversity was detected in Tatars from the Barabinsk forest steppe, Tobol-Irtysh Tatars, Kazakhs, and Bashkirs. The presence of the haplogroup B in the mitochondrial DNA genetic pool of Siberian Tatars brings them together with Turks that came from regions of Altai and Central Kazakhstan and inhabited the Western Siberian forest steppe in the 6th–9th centuries. The haplogroup U7, which is typical of populations of Jordan, Kuwait, Iran, and Saudi Arabia, could also have entered the territory of residence of Siberian Tatars in the middle of second millennium BC, when Iranian-speaking tribes entered Siberia.     

Polymorphism of the paraoxonase (<Emphasis Type="Italic">PON-1</Emphasis>) gene in the Slavonic part of the Kharkiv population

We studied the polymorphism of gene PON-1 in 192 positions of amino acid sequence of enzyme paraoxonase 1, which is connected with isoenzymes R and Q. We analyzed 109 blood samples of habitants of Kharkiv (78 men and 31 women), 84 Ukrainians and 25 Russians. The frequency of the Q allele was p _Q = 0.67, and R allele − p _R = 0.33. The differences among Ukrainians and Russians as well as among men and women were not significant. The genotype’s frequency distribution in the Slavonic part of the Kharkiv population corresponds to the panmictic population.     

A comparative evaluation of the pharmacokinetics of different forms of benzathine benzylpenicillin]

Comparative randomized opened pharmacokinetic evaluation of benzathine benzylpenicillin in three dosage forms was performed. Benzathine benzylpenicillin was used as extencilline (2.4 million U or 1.2 million U, "Rh?ne-Poulenc Rorer", France) and as bicillin-5 (1.5 million U, "Synthesis" Russia). 33 patients were included in investigation (23 women and 10 men aged 16-60 years). 25 persons had verified rheumatism without blood circulation failure signs, 4--had chronic tonsillitis and 4 were healthy volunteers. Benzylpenicillin concentration was estimated by microbiology test in blood samples taken at 1, 3, 24 hours and 7, 14 and 21 days after intramuscular drug injection. After 2.4 million U extencilline injection (12 patients) its concentration, was at the inhibition level for beta-hemolytic streptococcus group A (25 ng/ml) for 3 weeks-period in 83.3 per cent of patients. After 1.2 million U extencilline injection (10 patients) or 1.5 million U bicillin-5 injection (12 patients) the above mentioned concentration was achieved on the 21st day in 30 and 0 per cent of patients respectively. Thus the treatment with benzathine benzylpenicillin at the 1.2 million U dose in the form of extencilline or bicillin-5 doesn't provide adequate antistreptococcal concentration in blood in prolonged period and is not suitable for correct rheumatism prophylaxis in adult patients.     

Analysis of genetic diversity of population of Northern Eurasia from autosomal microsatellite loci

The paper presents the results of analysis of the gene pools of several North Eurasian ethnic groups (Buryats, Evenks, Altaians, Russians, Kyrgyzes, Tuvinians, Tatars, and Ukrainians) examined using a panel of autosomal microsatellite markers (D4S397, D5S393, D7S640, D8S514, D9S161, D10S197, D11S1358, D12S364, and D13S173) mapped on different chromosomes and represented by the (CA)n dinucleotide repeats. In the group of populations examined the proportion of genetic variability at microsatellite loci explained by interpopulation differences was about 2.5%, while genetic differences between the individuals within a population accounted for 97.5% of this variability. Analysis of genetic relationships among the populations revealed substantial differences between the populations belonging to the Indo-European and Altaic linguistic families in gene diversity at microsatellite loci.     

Analysis of insertion-deletion polymorphism in serotonin transporter gene in men of different ethnic appurtenance with acute alcoholic psychosis

Analysis of insertion-deletion polymorphism of serotonin vector gene (SLC6A4) was carried out in Russian and Tatar men with acute alcoholic psychosis. Significant interpopulation differences in the distribution of SLC6A4 genotype and allele frequencies were revealed. A relationship of L/S gene with the disease was detected in Russians and Tatars, but the presence of heterozygotic genotype was associated with early onset of chronic alcoholization and development of acute alcoholic psychosis in Tatars and with later alcoholization and disease development in Russians. The share of S/S genotype was significantly decreased in Russian patients aged over 35 years, which suggests selection aimed at elimination of short allele homozygotes among patients with this disease and probably different genetic prerequisites for early and late development of the disease in Russians. In Tatars aged over 35 years acute alcoholic psychosis is associated with L/L genotype (RR-3).     

Polymorphism of alcohol dehydrogenase gene ADH1B in eastern Slavic and Iranian-speaking populations

Frequencies of alleles and genotypes for alcohol dehydrogenase gene ADH1B (arg47his polymorphism), associated with alcohol tolerance/sensitivity, were determined. It was demonstrated that the frequency of allele ADH1B*47his, corresponding to atypical alcohol dehydrogenase variant in Russians, Ukrainians, Iranians, and mountain-dwellers of the Pamirs constituted 3, 7, 24, and 22%, respectively. The frequencies established were consistent with the allele frequency distribution pattern among the populations of Eurasia. Russians and Ukrainians were indistinguishable from other European populations relative to the frequency of allele ADH1B*47his, and consequently, relative to specific features of ethanol metabolic pathways. The data obtained provide refinement of the geographic pattern of ADH1B*47his frequency distribution in Eurasia.     

Hatching of common carp (Cyprinus carpio L.) embryos stored at 4 and -2 degrees C in different concentrations of methanol and sucrose

The hatching performance of common carp (Cyprinus carpio L.) embryos was examined after 12-72-h storage at 4 and -2 degrees C using different concentrations of sucrose (0.1, 0.25, 0.5 and 1.0 M or 3.42, 8.55, 17.10 and 34.2%), methanol (MeOH) (0.5, 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5 M or 1.6, 3.2, 4.8, 6.4, 8.0, 9.6 and 11.2%), or varying concentrations of methanol in 0.5 M (17.10%) sucrose. For sucrose, 0.5 M (17.10%) showed the maximum survival (41+/-1% (12 h) to 11+/-1.5% (72 h)) at 4 degrees C. No survival was observed at -2 degrees C with any concentration of sucrose. At both temperatures employed, hatching was higher with mixed combination of methanol (1.5 M or 4.8%) and 0.5 M (17.10%) sucrose (4 degrees C: 41+/-1.5% (12 h), 38+/-1.2% (72 h); -2 degrees C: 33+/-1.7% (12 h), 28+/-1.2% (72 h)) compared to methanol alone (4 degrees C: 38+/-1.5% (12 h), 35+/-2.5% (72 h); -2 degrees C: 31+/-2.5% (12 h), 25+/-2% (72 h)). The combination of 1.5 M (4.8%) methanol and 0.5 M (17.10%) sucrose produced the best results among all the concentrations tested at both temperatures.     

Endothelial nitric oxide synthase gene minisatellite polymorphism: study in populations of the Volga-Ural region and analysis of associations with myocardial infarct and essential hypertension]

The 27-bp tandem repeat polymorphism in intron 4 of the endothelial nitric oxide synthase gene (eNOS) in populations of the Volga-Ural region was studied by means of polymerase chain reaction. In Russians and Tatars, the possible association of this polymorphism with coronary heart disease complicated by either myocaridal infarction or by essential hypertension was examined. Russians with essential hypertension associated with hypertrophy of the left ventricle displayed a statistically significant increase of the eNOS4A/B genotype and the A allele frequencies along with the decrease of the frequencies of the eNOS4B/B genotype and the B allele. In Tatars survived from myocardial infarction and with the risk of cardiovascular diseases (smoking or burdened heredity), a statistically significant increase of the frequencies of the eNOS4A/B genotype and the A allele was observed. Thus, in Russians the eNOS4A/B genotype was associated with the development of essential hypertension, while in Tatars it was associated with the risk of myocardial infarction.