Aim: To evaluate whether estrogen receptor alpha (ER-alpha) and vitamin D receptor (VDR) genes are associated with the age at menarche in Chinese women.
Methods: A total of 390 pre-menopausal Chinese women were genotyped at the ER-alpha PvuII, XbaI, and VDR ApaI loci using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP).
Results: Neither the ER-alpha gene nor the VDR gene individually had significant effects on the age at menarche in our subjects (P>0.10). However, evidence of interaction effects between the two genes were observed: with the aa genotype at the VDR ApaI locus, subjects with haplotype PX at the ER-alpha gene had, on average, 6 months later onset of menarche than the non-carriers (P=0.01).
Conclusion: We found that neither the ER-alpha gene or the VDR gene had a significant association with the age at menarche individually. However, potential interaction effects between the two genes were observed in Chinese women.