Lack of association between vitamin D receptor genotypes and haplotypes with fat-free mass in postmenopausal Brazilian women.

摘要

The relationship between vitamin D receptor (VDR) ApaI, CDX2, BsmI, FokI, and TaqI polymorphisms and fat-free mass (FFM) were examined in 191 postmenopausal Brazilian women (mean age 67.87 +/- 5.22 years). Participants underwent FFM measurements by dual-energy x-ray absorptiometry (DEXA). Whole-blood-extracted genomic DNA was genotyped to the aforementioned polymorphisms and to ancestry-informative markers through minisequencing, using the SNaPshot Multiplex System. Association between VDR polymorphisms and FFM variables was assessed by analysis of covariance. Haplotypes were estimated, and regression-based, haplotype-specific association tests were carried out with the studied phenotypes. No departure from Hardy-Weinberg equilibrium was detected for any polymorphism. None of the investigated VDR allelic variations, individually or analyzed as haplotypes, was associated with FFM phenotypes. The inclusion of individual African genomic ancestry was used as an attempt to correct for population stratification. Further studies in larger sample population are required to confirm these findings.