Relationship Between Vitamin D Receptor Gene BsmI Polymorphism and 25-Hydroxyvitamin D Total Levels in Slovak Postmenopausal Women with Reduced Bone Mineral Density

<b>Objectives:</b> The BsmI polymorphism of the <i>VDR</i> gene (vitamin D receptor) is one of the important genetic variants influencing the development of osteoporosis. Measurement and evaluation of the 25-hydroxyvitamin D (25(OH)D) concentration in individuals with reduced bone mineral density are essential because deficiency of this hormone causes impaired bone mineralization, leads to low BMD (bone mineral density), and influences fracture formation. The aim of the study was to investigate the relationship between the <i>VDR</i> gene BsmI polymorphism and 25(OH)D levels in Slovak postmenopausal women. <b>Materials and Methods:</b> The study population consisted of 287 untreated postmenopausal women, who were divided into three groups based on T-scores: normal (CG = 65), osteopenia (OPE = 126), and osteoporosis (OPO = 96). DNA isolation was performed using a standard protocol. Genetic analyses of the BsmI (rs1544410) polymorphism of the <i>VDR</i> gene were performed using the TaqMan SNP genotyping assays. Biochemical analysis of total 25(OH)D was performed in blood serum using the electrochemiluminescence method. <b>Results:</b> The chi-square test confirmed that the mutant T allele was not associated with the development of osteoporosis (<i>p</i> = 0.419). Through Kruskal-Wallis analysis, we found significant differences (<i>p</i> < 0.05, <i>p</i> < 0.01) in total 25(OH)D concentrations in individual genotypes of the BsmI variant of the <i>VDR</i> gene between the groups of women studied. <b>Conclusions:</b> It can be concluded that the <i>VDR</i> gene and its variant BsmI as well as 25(OH)D total may be relevant markers in the etiology of the search for individuals at risk of osteoporosis.