Endocrine Abstracts

Polymorphism of the vitamin D receptor (VDR) gene has been reported to play a major role in variations for genetic regulation of bone mass. The current study is an attempt to examine the association of these variations with osteoporosis in patients with hypothyroidism. The purpose of this study was to determine distribution of genotypes and allelic frequencies of polymorphism of rs731236 (C+61968t; TaqI) VDR gene, and also risk of development and association with risk factors of bone mineral density changes in women with hypothyroidism.

Methods: There were 95 women with hypothyroidism under a supervision in age from 34 to 65 years. Exposure of vitamin D receptor gene polymorphism in vitro was produced by the method of PCR.

Results: The prevalence of mineral bone density disorders among patients with hypothyroidism was 46.3%, including with osteopenia 32 (33.7%) and osteoporosis in 12 (12.6%). Presence of homozygote on major allele VDR gene rs731236 (C+61968t; TaqI) possesses protective effect on development of osteoporosis, while the presence of homozygote on minor allele of this polymorphism of T/T assists to development of osteoporosis.

Conclusions: Presence of genotype major allele (C) is diminished with the 3.8 times greater risk of osteoporosis development, while presence of minor allele (T) is promoted with the 3.9 times greater risk. Presence in the genotype of homozygote on minor allele T/T combines with more expressed decline of mineral bone density. Minor allele (C) is associated with hypocalcemia, by the decline of bone mineral density, hyperphosphatemia, activation of osteocalcin.