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E Kobyliansky

Publications and source records attributed to E Kobyliansky.

At least 19 recordsLinked to original sources

Genetic and environmental determinants of circulating resistin level in a community-based sample.

OBJECTIVE: Resistin is a hormone secreted by adipose tissue, monocytes, bone marrow, and other tissues. It was also proclaimed as an important link between obesity and diabetes. The main objective of this study was to elucidate the contribution of a number of endogenous factors, such as sex, age, obesity characteristics, and genetic effects to the production of resistin in apparently healthy individuals. We also tested the possible relationships between circulating levels of resistin and other adipokines (leptin, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha)). MEASUREMENTS: The plasma levels of studied adipokines were determined by enzyme-linked immunoassay in pedigree-based sample (n = 616), and subjected to model-based quantitative genetic analysis. RESULTS: Resistin levels were significantly higher in women than in men (3.60 +/- 2.53 vs 3.15 +/- 2.48 ng/ml, P < 0.001), and varied independently of age in either sex. Statistical-genetic analysis revealed significant familial correlations (P < 0.01) for resistin. Adjusted for covariates, 66.38 +/- 10.28% of the resistin variation was attributable to putative genetic factors. A relatively small portion of the resistin variation (11.54 +/- 5.77%) was attributable to sharing a common household environment. The remaining variation, 22.12 +/- 17.69% was due to random environmental (i.e., unmeasured non-additive genetic) effects. The results of our analysis showed modest significant correlation of resistin with TNF-alpha and IL-6, and only in some groups; thus, while resistin was correlated with TNF-alpha in men, the correlation with IL-6 was significant only in the post-menopausal women group. CONCLUSIONS: Our observations indicate that resistin is strongly influenced by genetic factors. The high heritability estimates for resistin concentrations clearly suggest the continuing need for further molecular genetic investigations.

Adolescent↗

Osteoprotegerin plasma levels are strongly associated with polymorphisms in human homologue of the mouse progressive ankylosis (ANKH) gene.

Osteoprotegerin inhibits osteoclastogenesis and plays an important role in the control of bone resorption. However, the genetic mechanisms underlying regulation of OPG levels are currently not fully elucidated. The aim of the present study was to determine whether the ANKH gene, which plays a central role in bone mineralization, contributes to the genetic regulation of OPG levels. A family-based association study used a sample of 159 ethnically homogeneous nuclear families, comprising 556 apparently healthy individuals. Statistical analyses included family aggregation analysis of OPG variation and four types of transmission disequilibrium tests. Each individual was genotyped for 11 SNPs in the ANKH gene. Four TDTs consistently showed a highly significant association between OPG levels and the intronic SNP rs875525 located between exons 6 and 7. The combined p-value for four tests to reject the null hypothesis of no association was 0.0003. Furthermore, haplotypes generated between rs875525 and two additional neighbouring SNPs (rs2291943 and rs2288474) also revealed a significant association with OPG plasma levels (p < 10(-4)-10(-3)). ANKH genetic polymorphisms in the area between SNP rs2291943 and rs2288474 are strongly associated with OPG plasma levels. The molecular mechanism underlying this association is not obvious, and therefore these results should be regarded cautiously until they are confirmed in independent studies.

Adult↗

Sex- and age-related variations of the somatotype in a Chuvasha population.

The aim of this large, cross-sectional study was to describe the age- and sex-related variations of the somatotype, employing Heath and Carter's method, in a Chuvasha population residing in a rural region in central Russia. The investigated sample included 802 males aged 18-89 years (mean 46.9) and 738 females aged 18-90 years (mean 48.6). We evaluated the age and sex differences by one-way ANOVA with somatotype components as dependent variables and sex or age groups as grouping variables. Sex differences of somatotypes appear to be the strongest for endomorphy, with generally higher values in women. Endomorphy in males remained virtually unchanged after 30 years of age, but endomorphy in females kept increasing up to the 6th decade, and then subsequently decreased. Virtually no differences were noted in mesomorphy and a very small difference in ectomorphy between males and females aged 18-30 years. A reduction of sexual dimorphism in all somatotype components after age 70 was also observed. The largest difference of all somatotype components appeared between age groups 18-30 and 31-40 years. Thereafter, somatotypes remained practically unchanged. Mesomorphy continued to increase until the 5th decade in both sexes, while in females, endomorphy continuously increased until their 6th decade. In the 7th and 8th decades, a decrease in mean values was observed. Mesomorphy and ectomorphy showed opposite age-related trends. Results of our study clearly suggest that in physique investigations, the somatotypes need to be studied in each sex separately, and in studies of young people, they need also to be adjusted to age.

Adolescent↗

Contribution of the familial and genetic factors on monocyte chemoattractant protein-1 variation in healthy human pedigrees.

Monocyte chemoattractant protein-1 (MCP-1) is a chemokine whose circulating levels have been detected in the lesions of several diseases such as pulmonary fibrosis, rheumatoid arthritis and atherosclerosis. However, the factors involved in the regulation of its production remain largely unknown. The main aim of the present paper was to ascertain the contribution of the familial/genetic factors on the production of MCP-1 in apparently healthy individuals. We also tested the possible relationships between the plasma levels of MCP-1 and other cytokines involved in bone metabolism (receptor activator NF-kB ligand (RANKL), osteoprotegerin (OPG), interleukin-6, macrophage-colony stimulating factor, tumor necrosis factor-alpha). Using ELISA assays the cytokine levels were measured in 570 apparently healthy individuals belonging to ethnically homogeneous Caucasian families. We found that MCP-1 levels were significantly (P<0.01) correlated with RANKL (in both sexes) and with OPG only in women. The study showed that adjusted for potential covariates, 72% of the MCP-1 variance, was attributable to familial effects. About 49% was due to potential genetic factors and the rest was explained by common environmental sources shared by spouses within each family. In conclusion, our data provide reliable evidence for the substantial role of genetic factors in the determination of the phenotypic variability of MCP-1 plasma levels. The association between the osteoclastogenic cytokines and MCP-1 levels in healthy pedigrees is of special interest and might shed light on MCP-1 involvement in bone remodeling.

Adult↗

Asymmetry and diversity of dermatoglyphic traits: population comparison in five endogamous groups of West Bengal, India.

Five different endogamous populations encompassing the main social ranks in the caste hierarchy of West Bengal, India were analyzed. To compare variability in populations with contrasting ethnohistorical backgrounds, analysis of variance, Scheffe's test and cluster analysis were performed, as based on dermatoglyphic variables, namely, 22 quantitative traits and 36 indices of diversity and asymmetry. The present study reveals that: 1. Overall disparities among the 5 populations are expressed only in finger ridge counts on the Ist and Vth digits and PII, in a-b ridge counts, in endings of main lines A and D, and in MLI on the palms; 2. Heterogeneity is greater in fluctuating asymmetry than in directional asymmetry; 3. There is a greater heterogeneity in the 22 quantitative traits than in the 36 indices of diversity and asymmetry, with females contributing more than the males; 4. The highest contribution to population variation is by Lodha among five populations; 5. Inter-group variations are homogeneous in most of the variables, which does not correspond with the relationships to caste hierarchy of these populations; 6. The dendrograms based on dermatoglyphic variables demonstrate that the traditional grouping of Indian populations, based on caste hierarchy, may not be a reflection of their genetic origin, in that the pattern of clustering corresponded best with the known ethnohistorical records of the studied populations; 7. Hence, dermatoglyphic affinities may prove quite useful in tracing the ethnohistorical background of populations.

Dermatoglyphics↗

Heritability of circulating growth factors involved in the angiogenesis in healthy human population.

The present study examined the extent of genetic and environmental influences on the populational variation of circulating growth factors (VEGF, EGF) involved in angiogenesis in healthy and ethnically homogeneous Caucasian families. The plasma levels of each of the studied biochemical indices were determined by enzyme-linked immunoassay in 478 healthy individuals aged 18-75 years. Quantitative genetic analysis showed that the VEGF and EGF variation was appreciably attributable to genetic effects, with heritability estimates of 79.9% and 48.4%, respectively. Yet, common environmental factors, shared by members of the same household, also played a significant role (P < 0.01) and explained between 20.1% and 32.6% of the variation. The present study additionally examined the covariations between these molecules and either transforming growth factor-beta 1 (TGF-beta 1) or tissue inhibitors of matrix metalloproteinases 1 (TIMP-1), likewise relevant for angiogenesis. Bivariate analysis revealed significant phenotypic correlations (P < 0.002) between all pairs of variables, thus indicating the possible existence of common genetic and environmental factors. The analysis suggested that the pleiotropic genetic effects were consistently the primary (or even the sole) source of correlation between all pairs of studied molecules. The results of our study affirm the existence of specific and common genetic pathways that commonly determine the greater part of the circulating variation of these molecules.

Adult↗

The contribution of familial resemblance to variation in circulatory levels of tissue inhibitors of metalloproteinases and transforming growth factor-beta1.

This study attempted to elucidate the genetic and environmental factors influencing interindividual variation of circulating TIMP-1, TIMP-2 and TGF-beta1 and to clarify the relationship between the latter biochemical indices and hand osteoarthritis in an ethnically homogeneous sample. Plasma levels of each of the above biochemical indices were measured in 401 healthy individuals (aged 18-75 years) belonging to 90 nuclear and more complex families. Variance component analysis showed that a major part of the interindividual differences in TGF-beta1, TIMP-1 and TIMP-2 levels was credibly attributable to genetic and familial factors. Adjusted for significant covariates, the putative genetic effects on the above three amounted to 0.40 +/- 0.10, 0.47 +/- 0.11 and 0.72 +/- 0.10, respectively. Common environmental factors, shared by members of the same household, also contributed significantly ( P < 0.01) to variation of each of the biochemical indices and explained between 27.6% (TIMP-2) and 38.7% (TGF-beta1) of their variation. A bivariate analysis revealed a strong and highly significant correlation between TIMP-1 and TGF-beta1 (r = 0.58, P < 0.001), which was due to common genetic and environmental sources (r(G) = 0.62 +/- 0.09, r(E) = 0.31 +/- 0.11, both P < 0.001). The analysis also detected modest but significant genetic correlation between TIMP-1 and TIMP-2 (r(G) = -0.307 +/- 0.108, P < 0.01). The present study evinces a strong genetic dependence for the plasma levels of both TIMPs and TGF-beta1 and provides a basis for the further analysis of genetic variation affecting and regulating the circulatory concentrations of TIMPs and TGF-beta1 in healthy humans.

Adolescent↗

Association and linkage disequilibrium analyses suggest genetic effects of estrogen receptor alpha and collagen IA1 genes on bone mineral density in Caucasian women.

Estrogen receptor alpha (ER alpha) and collagen IA1 (COLIA1) genes have been suggested as possibly implicated in reduced bone mineral density (BMD). The present study investigated the occurrence of association and linkage disequilibrium between radiographic hand BMD and polymorphic alleles of ER alpha and COLIA1 genes, in human pedigrees of a Chuvasha population in Russia. The study sample included 463 members of 113 pedigrees, mostly nuclear families. We performed association and transmission disequilibrium test (TDT) analyses of the combined PvuII and XbaI RFLPs alleles on the same chromosome (haplotype) of the ER alpha gene with BMD Z scores of cancellous or cortical bone in the hand phalanges. The association analyses were performed separately for both genders in the parental generation, i.e., 'fathers' (n = 114; average age 64.2 y) and 'mothers' (n = 122; average age 62.7 y). The Px haplotype was associated significantly with lower BMD Z scores in 'mothers' only. The difference between subjects who carried one or two copies of the Px haplotype and those lacking it was 0.68 Z scores, P = 0.003 and 0.51 Z scores, P = 0.025 for cancellous and cortical bone, respectively. Multiple linear regression model with age, height, weight, and Px haplotype status as predictors explained 26.7% and 28.3% of the total observed variance in BMD with Px haplotype as independent predictor explaining 5.9%; P = 0.002 and 3%; P = 0.028 (cancellous and cortical bone, respectively). Results of t-TDT for triads of two parents and just one of their female offspring (but not male offspring) suggested the existence of linkage disequilibrium between the two loci of Px haplotype and BMD trait (P = 0.047). No association was found between polymorphic alleles of COLIA1 gene and BMD, but 'mothers' with combined genotypes of Px haplotype of ER alpha gene and "s" allele of COLIA1 gene had the lowest mean Z scores (-0.944 and -0.788 for cancellous and cortical bone, respectively). We conclude that the Px haplotype of the ER alpha gene is associated with low BMD values in females, as the phenotype is gender dependent (the association was not observed in males), and the "s" allele of COLIA1 gene in combination with this haplotype contributes to reduced BMD.

Adolescent↗

Genetic effects of estrogen receptor alpha and collagen IA1 genes on the relationships of parathyroid hormone and 25 hydroxyvitamin D with bone mineral density in Caucasian women.

There is a growing body of evidence that estrogen receptor alpha (ERalpha) and collagen IA1 (COLIA1) genes may affect bone mineral density (BMD) levels in postmenopausal women. In a recent study we found that the Px haplotype of the ERalpha gene (resulting from combined PvuII and XbaI restriction fragment-length polymorphisms [RFLPs] in intron 1) was associated with low radiographic phalangeal hand BMD in elderly women (62.7 +/- 6.5 years of age), of European origin. The combination of the Px haplotype and "s" allele of the COLIA1 gene (MscI RFLP in Sp1 locus) decreased BMD in these women. The major aim of the present study was to investigate whether the genetic effects of these genotypes on cancellous and cortical hand BMD, in the same elderly women (N = 122), are possibly mediated through circulating levels of parathyroid hormone (PTH) and/or 25 hydroxyvitamin D [25(OH)D], and may be related to biochemical markers of bone turnover (propeptide of type I procollagen [PICP] and osteocalcin). Multiple regression analyses of age-adjusted cancellous BMD revealed that ERalpha polymorphism and circulating levels of PTH were independent predictors of about 12.9% of its variation. Some 17.9% of cortical BMD variations were attributable to the combined effects of ERalpha polymorphism and plasma concentrations of 25(OH)D, estradiol, and PTH. The significant inverse association between PTH and BMD of both types was further confirmed by association analysis according to categorical subgroups of BMD values, as well by haplotype status. The mean difference in PTH concentrations between subjects carrying the Px haplotype (higher mean) and those lacking it (lower mean) reached 0.59 SD (P =.01). The difference in PTH levels further increased when explored in the 4 subgroups formed by combinations of polymorphic ERalpha and COLIA1 genotypes. Mean PTH of subjects carrying both the Px haplotype and "s" allele was higher by 1.52 SD (P =.001) than in subjects lacking both the Px haplotype and "s" allele. Those carrying both Px haplotype and "s" allele were also characterized by highest mean value of PICP and lowest means of 25(OH)D and BMD (both tissue types). We conclude that in the studied elderly women, the Px haplotype may be involved in causing the phenotypic expression of higher circulating levels of PTH and higher bone turnover, which, in turn, may lead to bone loss.

Aged↗

Search for linkage between hand osteoarthritis and 11q 12-13 chromosomal segment.

OBJECTIVE: The aims of the present study were: (1) to evaluate the extent and mode of inheritance of hand osteoarthritis by using a large sample of ethnically homogeneous pedigrees of Caucasian origin; (2) to examine whether the synthetic measure of osteoarthritis according to Kellgren and Lawrence (K-L) and the more specific measure, namely, the extent of osteophytes development, have a similar putative genetic determination and pattern of biological inheritance and (3) to test the hypothesis that hand osteoarthritis dependent phenotypes are linked to the 11q 12-13 chromosomal region. METHODS: The population of the present study comprised 1190 Chuvashians (Russian Federation) belonging to 295 nuclear families. Segregation analysis was carried out on a total sample. Sub-sample of 571 individuals was used to conduct Transmission/disequilibrium test (TDT) and model-based linkage analysis. RESULTS: Adjusted for age, sex and other covariates, both OA phenotypes showed significant familial aggregation. The model fitting analysis strongly supported the hypothesis of a major gene effect on study traits. The inferred major gene explained about 52% of the osteophyte score (OPS) and 49% of the K-L score variation adjusted for confounding variables. The series of model-based linkage analyses and TDTs provided inconclusive evidence on possible linkage of both phenotypes to the 11q 12-13 chromosomal region. CONCLUSIONS: We support the hypothesis of a major gene effect in heritability of hand osteoarthritis in both phenotypes. Despite the fact that some DNA markers showed statistically significant association to studied primary phenotypes, we find only weak evidence of linkage disequilibrium between hand osteoarthritis and the proximal part of the 11q 12-13 chromosomal segment (D11S1983 for K-L score and D11S1313 for OPS). The subject, however, a merit requires further investigation.

Adolescent↗

Quantitative genetic study of radiographic hand bone size and geometry.

Despite the obvious epidemiological significance of bone size (BS) and geometry (BG) traits as risk factors for osteoporotic fracture, very little is still known concerning the extent of their genetic determination. In the present paper we report the results of quantitative genetic analysis of a number of BG and BS indices, as well as of BMD measurements, obtained on a large pedigree-based sample (296 nuclear families, 1208 individuals) of plain hand radiographs. The families studied were all ethnically Caucasians (Chuvasha) living in small villages along the Volga River (Russia). The sample consisted of 636 men and 572 women, aged 18-91 years. To assess hand bone size we used the outcome of principal component analysis conducted on 48 measurements of metacarpal bones and proximal phalanges (PC-BS). Two BG indices, average metacarpal cortical index and breaking bending resistance index (BBRI), also measured on metacarpal and proximal phalanges were used. Again the outcome of the principal component PC-BBRI was examined in the genetic analysis. PC-BS measurements strongly correlated with body length (r = 0.75, P < 0.001) and weight (r = 0.39, P < 0.001), suggesting that they indeed reflected hand skeleton size. Familial correlations for all studied traits, adjusted for covariates (sex, age, etc.), were all highly significant statistically. For example, parent/offspring correlations ranged between 0.248 (P < 0.001) for phalangeal BMD and 0.385 (P < 0.001) for PC-BBRI. Maximum likelihood estimates of the variance component analysis confirmed these results, indicating that approximately 58 to 66% of the residual variance of the studied traits was attributable to genetic effects. Bivariate analysis clearly revealed that while genetic variation of the phalangeal BMD was independent of the genetic effects influencing hand BS and BG, the latter two were strongly interrelated. A substantial proportion of PC-BS and PC-BBRI variation was due to shared genetic (r(G) = 0.468 +/- 0.063) and environmental (r(E) = 0.704 +/- 0.052) factors.

Adolescent↗

Multivariate analysis of sexual dimorphism in two types of dermatoglyphic traits in five endogamous populations of West Bengal, India.

Five different endogamous populations who encompass the main social rank in the caste hierarchy of West Bengal were analysed for this report. The present approach is to compare the pattern of sex differences/similarities exhibited by two different sets of dermatoglyphic traits. Cluster and discriminant analysis and Mantel test of matrix correlations were performed. The nature of variation between sexes within population groups and two types of variable sets has a good similarity in all five populations. These results strongly suggest that the two categories of dermatoglyphic variables provide similar possibilities to discriminate between the sexes in populations.

Adult↗

Transmission disequilibrium test for hand bone mineral density and 11q12-13 chromosomal segment.

The main aim of the present study was to test the hypothesis that the bone mineral density (BMD) assessed from radiographs of the hand phalanges in a random sample of ethnically homogeneous pedigrees is linked to the 11q12-13 chromosomal segment. The data for the study were gathered from 574 Chuvasha individuals belonging to two- and three-generation pedigrees who live in small villages in the Bashkortostan autonomy, Russia. Preliminary statistical-genetic analysis of the BMD in the pedigrees studied showed that potential genetic effects were highly significant ( p<0.001, in comparison with the model assuming no genetic effect), and explained at least 36% of the BMD variation adjusted for sex and age differences. For the transmission/disequilibrium test (TDT) used in our study, a total of 163 nuclear families with two sibs on average were available. Seven DNA microsatellite markers ( D11S1313, D11S1765, D11S987, D11S913, D11S983, D11S1314, D11S916) with average spacing of 2 cM on the chromosomal area 11q12-13 were selected for the TDT. The nominal p values ( p<0.05-0.0015) obtained from three TDT-type tests used for random and extreme-threshold sampling designs pointed consistently to possible linkage disequilibrium between BMD and some of the DNA markers. There was evidence for possible linkage disequilibrium in the upper part of the chromosomal segment studied (markers D11S1313 and D11S1765), and also in the lower part (markers D11S1983 and D11S1314). The lowest nominal p values (0.0015-0.0067) were obtained from three TDT-type tests for marker D11S1313. However, our findings must still be treated with great caution.

Adult↗

Dermatoglyphic sexual dimorphism: finger and palmar qualitative characteristics in five endogamous populations of West Bengal, India.

Five hundred families from five different endogamous populations encompassing the main social rank in the caste hierarchy of the same geographical area of West Bengal, India, were analyzed to present variation in qualitative pattern types on fingers and palms. Sex dimorphism, homogeneous in all populations, suggests common characteristics of dermatoglyphic patterns. The pattern types are not uniformly distributed on 10 fingers and palmar configurational areas. However, most of these observations are homogeneous in nature, in both sexes among 5 populations. But the two sets of results on fingers and palms are not exactly the same. Palmar dermatoglyphic relationship reflects the better caste affinities, perhaps due to embryological development, having relatively a longer growth period compared to fingers (Cummins 1929). The present findings indicate that the qualitative dermatoglyphic affinities conform to the known ethnohistorical background of these populations, which correspond also to the results of quantitative dermatoglyphics as well as serological and biochemical markers of these populations. These observations indicate that these population groups have a common genetic background and thus traditional grouping of Indian populations on the basis of caste hierarchy may not be a reflection of the genetic origin of the population. In dermatoglyphic affinities, both qualitative and quantitative traits therefore may be quite useful in tracing the ethnohistorical background of these populations.

Consanguinity↗

Relationship between genetic anomalies of different levels and deviations in dermatoglyphic traits. Part 7: Dermatoglyphic peculiarities of females with cervical and endometrial carcinoma.

This study was carried out to evaluate the effects of neoplastic diseases like carcinoma of the cervix and endometrial carcinoma, and was based on dermatoglyphic traits and their indices of intraindividual diversity (Div), fluctuating asymmetry (FIA) and directional asymmetry (DA). The results were compared with control groups of women and men, whose data have been detailed in our previous publications (Kobyliansky et al., 1999 a-d), and with analogous data of additional cancer groups available in the literature, like acute leukemia, bronchial cancer and breast cancer. The general aims of the study were as follows: (a) to obtain a dermatoglyphic characterization of discrete and quantitative traits and their Div, DA, FIA values in cancer patients, compared to healthy control groups, both female and male; (b) to test the hypothesis that in cancer patients there is an increased level of FIA as a result of an impaired developmental homeostasis; (c) to explore the possibility of using DT (dermatoglyphic traits) data of CW (women with cancer) to predict the probability of the appearance of cervical and endometrial carcinoma in apparently healthy females at a young age. The sample consisted of 94 Israeli-Jewish women of various groups, of which 54 had endometrial carcinoma and 40 had cervical carcinoma. The prints were collected in the Tel-Hashomer Hospital. The control group was a sample of 874 healthy subjects, half of them male and the other female, all from Jewish communities of European extractions (50%) as well as from Africa (50%). All controls were adults (over 18 years of age). Interpretation of prints was performed according to Cummins & Midlo (1961) and Penrose (1968) and included identification of patterns, ridge counts and the measurement of distances and angles in the palms, 79 DT for every individual were assessed. Significant differences were found for some of the studied traits between cancer patients and their healthy control groups. We encountered merely a low sexual dimorphism between the CW and the control males as compared to that between control males and females (with significant differences in 18% of the quantitative traits vs 64% in the control). The indices of diversity and asymmetry proved more suitable for discrimination, yielding the highest discrimination level between CW and control females. This finding suggested other data in the present study which points to a similarity between CW and control males.

Adult↗

Sexual dimorphism: asymmetry and diversity of 38 dermatoglyphic traits in five endogamous populations of West Bengal, India.

Five hundred families from five different endogamous populations encompass the main social rank in the caste hierarchy of West Bengal, India were analyzed for the present report. With the aim of comparing dermatoglyphic sexual dimorphism among the groups, analysis of variance and principal component analysis were performed, based on 38 dermatoglyphic variables. Sex dimorphism is homogeneous in nature in all populations, indicating common characteristics of dermatoglyphic variables within the same geographic area. But sex differences display different levels when compared with other racial groups. Therefore, sex differences are different in diverse populations. This would explain the existence of the possible role of environmental prenatal factors in the realization of the level of dermatoglyphic sex differences. Sex differences in asymmetry indices are less pronounced, which indicates that Indian populations are less asymmetric compared to Jewish populations. Fluctuating asymmetry, which is greater in females compared to males, support the hypothesis of Livshits and Kobyliansky--"increased heterozygosity is often associated with a decreased phenotypic variability including a diminished fluctuating asymmetry". A common feature of the principal component factor 1 "digital pattern size factor", in diverse populations indicates its degree of universality, and suggests that the variability of finger ridge counts is determined by the same genes which control the pattern types. The factors "finger ridge count diversity factor", "directional asymmetry factor", "fluctuating asymmetry factor", and "bilateral asymmetry factor" was perhaps described in the literature for the first time in Indian populations. The nature of variation of these components among these populations and between sexes, appears with a good similarity which suggests their biological validity of the underlying component structure. The overall homogeneity of sex dimorphism among 5 populations is well pronounced.

Adult↗

Bone mineral density is associated with estrogen receptor gene polymorphism in men.

In order to identify genetic effects of allelic variation on bone mineral density (BMD), association studies have been performed recently. Examining the relation between PvuII and XbaI restriction fragment length polymorphism (RFLPs) at the estrogen receptor (ER alpha) gene and BMD, in women or men, have yielded conflicting results. We analyzed the association between this polymorphism and BMD Z score values of cancellous bone at the 3rd finger in 344 members of nuclear families of European population, Chuvasha, living in Russia. The population sample included 183 males, aged 18-84, and 161 females, aged 23-79. The analysis has been performed separately for both sexes and for both generations (parents and offspring). We used a novel direct haplotyping method, which determines simultaneously each of the PvuII and XbaI RFLPs and their relation to each other. The haplotypes were represented as the combination of both polymorphic sites on the same chromosome, by using P/p and X/x for PvuII and XbaI restriction sites, respectively. The subjects were classified into 3 groups of genotypes: A = PXPX (homozygote for the PX haplotype); B = PXPx, PXpx (the heterozygotes for the PX haplotype); C = PxPx, Pxpx, pxpx (genotypes that are lacking the PX haplotype). The PXPX genotype (A) was associated with higher BMD Z score values in comparison to the genotypes that are lacking the PX haplotype (C), in total males [0.618 vs. -0.133 (p = 0.004)] and for the "sons" generation [0.724 vs. -0.198 (p = 0.02)]. Similar tendency was observed for the "fathers" generation (0.539 vs. -0.085), though the difference did not approach statistical significance (p = 0.087). These findings were not found in the female samples, nor in the "mothers" or "daughters" generations. The question if there are differences in the mode of action of estrogen through its receptor on bone mass, between the genders or between the males' generations, have to be further investigated.

Adolescent↗