CER 1 gene polymorphism in postmenopausal Roma and non-Roma Slovak women in connection with osteoporosis.

OBJECTIVE: The aim of our study was to investigate the relationship between the rs74434454 polymorphism of the CER1 gene and selected biochemical, densitometric and anthropometric markers in Slovak postmenopausal women of two ethnic groups: Roma and non-Roma. SUBJECTS AND METHODS: The scientific study included 303 postmenopausal women of the non-Roma and Roma populations who were divided into two groups based on densitometric measurements: control group (CG) and osteoporotic group (OG). Genomic DNA was isolated from peripheral blood using a commercial NucleoSpin® Blood kit following a standard protocol. The TaqMan Real-Time PCR method was used for genotyping. Biochemical markers were measured with Cobas e411 and Cobas Integra400 plus analysers. RESULTS: In the control group of postmenopausal Roma women, the occurrence of the risk genotype GG was not observed. In the group of Roma women with osteopenia and osteoporosis, the GG genotype occurred at a frequency of 3.03%. In the group of non-Roma women (between CG and OG) statistically significant differences were found in all monitored biochemical markers except CTx-I (p<0.66). In contrast, in the group of Roma women, statistical significance was only found in the osteoresorption marker CTx-I (p<0.007). In the population of Roma women, we did not find a statistically significant difference between the AA, AG and GG genotypes in any of the monitored markers. CONCLUSIONS: The results provide the first and unique insight on the distribution of genotypes and alleles of the rs74434454 CER1 gene polymorphism and its relationship to markers of bone metabolism in two ethnically distinct groups.

Preliminary results of ethnic divergence of G1181C (rs2073618) and C290T (rs9525641) OPG gene polymorphisms in groups of postmenopausal Slovak women.

OBJECTIVE: In this study, we focused on observation of the genetic polymorphisms of the OPG genes G1181C (rs2073618) and C290T (rs9525641), their interactions with biochemical markers and anthropometric parameters in groups of postmenopausal Slovak women (Roma and non-Roma, n = 311). PATIENTS AND METHODS: Genomic DNA was extracted and purified from peripheral blood leukocytes by the kit Ultraclean® Blood non-spin® (Carlsbad, CA, USA) using a standard protocol. Genotyping was performed by the TaqMan SNP genotyping assay. Biochemical markers were measured by the Cobas e411 (Roche Diagnostic, Tokyo, Japan) and Cobas Integra400 plus (Roche Diagnostic, Rotkreuz, Switzerland) analysers. RESULTS: We recorded a higher frequency of the T allele in the C290T polymorphism of the non-Roma control group (53.846%), in Roma groups: control (T - 56.618%) osteoporotic (T - 51.471%). In the G1181C polymorphism, the CC genotype occurred more in the osteoporotic group (34.286%) compared to the control group (27.885%). In the group of postmenopausal Roma women, a statistically significant difference (p<0.05) was found between osteoporotic and control in the biochemical parameters' osteocalcin, C-terminal telopeptide I, and age. Statistically significant differences (p<0.0001) were also found in bone mineral density and T-score. The high odds ratio suggests the association of G1181C with osteoporosis. A close relationship was found between haplotypes, BMD, T-score, and IL-6 in control; and BMI, WHR, T-score, and osteocalcin in osteoporotic groups of Roma and non-Roma women. CONCLUSIONS: The results point to differences in the occurrence of genotypes and associations of haplotypes with the manifestation of osteoporosis in Roma and non-Roma women. However, a larger number of samples is needed to determine whether or not there are differences between the Roma and non-Roma populations.

WNT10A variants in relation to nonsyndromic hypodontia in eastern Slovak population.

Nonsyndromic hypodontia is a congenital absence of less than six permanent teeth, with a most common subtype maxillary lateral incisor agenesis (MLIA). Mutations in several genes have been described in severe tooth agenesis. The aim of this study was to search for the variants in wingless-type MMTV-integration site family member (WNT10A), paired box 9 (PAX9) and axis inhibitor 2 (AXIN2) genes, and investigate their potential role in the pathogenesis of non-syndromic hypodontia. Clinical examination and panoramic radiograph were performed in the cohort of 60 unrelated Slovak patients of Caucasian origin with nonsyndromic hypodontia including 37 MLIA cases and 48 healthy controls. Genomic DNA was isolated from buccal swabs and Sanger sequencing of WNT10A, PAX9 and AXIN2 was performed. Altogether, we identified 23 single-nucleotide variants, of which five were novel. We have found three rare nonsynonymous variants in WNT10A (p.Gly165Arg; p.Gly213Ser and p.Phe228Ile) in eight (13.33%) of 60 patients. Analysis showed potentially damaged WNT10A variant p.Phe228Ile predominantly occurred only in MLIA patients, and with a dominant form of tooth agenesis (odds ratio (ORdom) = 9.841; P = 0.045; 95% confidence interval (CI) 0.492-196.701;ORrec = 0.773; P = 1.000; 95% CI 0.015-39.877). In addition, the WNT10A variant p.Phe228Ile showed a trend associated with familial nonsyndromic hypodontia (P = 0.024; OR= 1.20; 95% CI 0.97-1.48). After Bonferroni correction, these effects remained with borderline tendencies. Using a 3D WNT10A protein model, we demonstrated that the variant Phe228Ile changes the proteinsecondary structure. In PAX9 and AXIN2, common variants were detected. Our findings suggest that the identified WNT10A variant p.Phe228Ile could represent risk for the inherited nonsyndromic hypodontia underlying MLIA. However, further study in different populations is required.

The ogd1 and kgd1 mutants lacking 2-oxoglutarate dehydrogenase activity in yeast are allelic and can be differentiated by the cloned amber suppressor.

The activity of mitochondrial 2-oxoglutarate dehydrogenase in S. cerevisiae can be impaired either by the ogd1 or the kgd1 mutation. The OGD1 gene and two suppressor genes were isolated by complementation of the ogd1 mutant. The complementation of the kdg1 mutant by the OGD1 gene, an allelism test, and meiotic mapping, revealed that the ogd1 and kgd1 mutations are allelic. The two mutations were differentiated by the cloned suppressor gene which was able to partially complement ogd1, but not kgd1. The molecular analysis of the suppressor gene revealed its identity with the natural tRNA(GlnCAG) gene found in the upstream region of URA10.