[Polymorphism of the gene for vitamin D receptor, bone mass, and bone turnover in women with postmenopausal osteoporosis]. / Polimorfismo del gen del receptor de la vitamina D, masa ósea y recambio óseo en mujeres con osteoporosis postmenopáusica.

ABSTRACT

OBJECTIVE: To analyze which genotypes of vitamin D receptor (VDR) are associated with the loss or maintenance of bone mass among spanish postmenopausal women. MATERIAL AND METHODS: A total of 105 women with postmenopausal osteoporosis and 51 postmenopausal women without osteoporosis (control group), diagnosed with bone densitometry (DEXA) were included in the study. The genetic locus was analyzed with RFLP by using the restriction enzyme BsmI. The obtained polymorphism was correlated with clinical, densitometric and metabolic parameters (including bone turnover markers). RESULTS: Two alleles were obtained with three bands of different size one 580-570 bp band corresponding to allele B, and two 405-400 and 175-170 bp bands for allele b. None of the three VDR genotypes (BB, bb, Bb) was significantly associated with a higher or lower bone mass among the studied populations. Likewise, in the group of patients with osteoporosis no genotype was associated with bone mineral density (BMD) values or with bone turnover parameters analyzed. No differences were found between subgroups with non-severe (n = 58) and severe (n = 47) osteoporosis regarding the association with any of the three VDR genotypes. CONCLUSIONS: None of the VDR genotypes was associated with BMD loss or with the activity of bone turnover parameters analyzed in a group of spanish women with postmenopausal osteoporosis. None of the VDR genotypes confers a higher susceptibility to suffer from severe osteoporosis.