Estrogen receptor α and vitamin D receptor gene polymorphisms and bone mineral density: association study of healthy pre- and postmenopausal Chinese women

Abstract

In the present study, we tested the association between the estrogen receptor α (ER-α) and vitamin D receptor (VDR) genes with bone mineral density (BMD). A total of 649 healthy Chinese women, classified as pre-menopausal ( N=388) and post-menopausal ( N=261) groups, were genotyped at the ER-α PvuII, XbaI, and VDR ApaI sites. BMDs at the lumbar spine (L 1–L 4) and total hip were measured by dual-energy X-ray absorptiometry. For the VDR ApaI locus, AA carriers had lower spine BMD than Aa ( p=0.02) and aa carriers ( p<0.01) in the pre-menopausal group. For the ER-α gene, carriers of haplotype px had lower spine BMD than the non-carriers ( p=0.03) in the pre-menopausal group. Furthermore, we observed significant interaction between the ER-α and VDR genes in the post-menopausal group: with AA genotype (or A allele) at the VDR ApaI locus, pX carriers had higher spine BMD than the non-carriers ( p=0.02), and PX carriers had lower hip BMD than the non-carriers ( p=0.04). Our data suggest that the ER-α and VDR genes may be associated with the BMD variation in Chinese women.