Association analysis of genetic polymorphisms and potential interaction of the osteocalcin (BGP) and ER-alpha genes with body mass index (BMI) in premenopausal Chinese women.

Aim: To investigate whether estrogen receptor alpha (ER-alpha) PvuII and osteocalcin (also known as bone Gla protein, or BGP) HindIII genetic polymorphisms and their potential interactions are associated with body mass index (BMI) variation.

Methods: Data on BMI and ER-alpha PvuII and BGP HindIII genotypes were obtained from 328 healthy premenopausal Chinese women in east China. The study subjects were unrelated, at least 21 years old (mean age of 33.2+/-5.9 years), and had an average BMI of 21.58+/-2.59. All subjects were genotyped at the ER-alpha PvuII and BGP HindIII loci using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP).

Results: The BGP HindIII genotypes were significantly associated with BMI (P=0.003). Carriers of the HH and Hh genotypes had approximately 2.73% and 1.27% higher BMI than those of the hh genotype, respectively. In contrast, the ER-alpha PvuII polymorphism was not significantly associated with BMI (P=0.454). In addition, there was no evidence of potential interactions between the ER-alpha and BGP genes in our subjects (P>or=0.013).

Conclusion: The HindIII polymorphism of the BGP gene, but not the PvuII polymorphism of the ER-alpha gene or their potential interaction, was associated with BMI in premenopausal Chinese women.