OBJECTIVE - To examine the relationship between genetic polymorphisms of the CYP19A1 gene and obesity-related phenotypes, body mass index (BMI) and waist-to-hip ratio (WHR).
SUBJECTS - In total, 1241 Chinese women, who were recruited as community controls for a population-based case-control study of breast cancer.
METHODS - Nineteen haplotype tagging single nucleotide polymorphisms (htSNPs) in four haplotype blocks were genotyped.
RESULTS - Significant associations were observed for WHR at three SNPs that are located in haplotype block 1, including rs2445765, rs1004984 and rs1902584 (P=0.05, 0.04 and 0.01, respectively). Women, particularly premenopausal women, who carried the minor allele at any of these SNPs, had higher WHR than those without it. Of these three SNPs, the strongest association was observed at rs1902584, which is the closest to Promoter I.4, the major promoter for adipose tissue. Haplotype analyses indicated an association between the haplotype TCCAT in block 1 and WHR with a P-value of 0.02.
CONCLUSION - These results suggested that CYP19A1 genetic polymorphisms may be associated with the risk of obesity among Chinese women, especially among premenopausal women. The CYP19A1 protein (aromatase) plays a critical role in estrogen biosynthesis and thus affects body fat distribution and regulation.