Genome-wide association study of bone mineral density in premenopausal European-American Women and replication in African-American women

Context: Several genome-wide association studies (GWAS) have been performed to identify genes contributing to bone mineral density (BMD), typically in samples of elderly women and men. Objective: The objective of the study was to identify genes contributing to BMD in premenopausal women. Design: GWAS using the Illumina 610Quad array in premenopausal European-American (EA) women and replication of the top 50 single-nucleotide polymorphisms (SNPs) for two BMD measures in African-American (AA) women. Subjects: Subjects included 1524 premenopausal EA women aged 20-45 yr from 762 sibships and 669 AA premenopausal women aged 20-44 yr from 383 sibships. Interventions: There were no interventions. Main Outcome Measures: BMD was measured at the lumbar spine and femoral neck by dualenergy x-ray absorptiometry. Age- and weight-adjusted BMD values were tested for association with each SNP, with P values determined by permutation. Results: SNPs in CATSPERB on chromosome 14 provided evidence of association with femoral neck BMD(rs1298989, P=2.7x10^-5; rs1285635, P=3.0x10^-5) in the EA women, and some supporting evidence was also observed with these SNPs in the AA women (rs1285635, P = 0.003). Genes identified in other BMD GWAS studies, including IBSP and ADAMTS18, were also among the most significant findings in our GWAS. Conclusions: Evidence of association to several novel loci was detected in a GWAS of premenopausal EA women, and SNPs in one of these loci also provided supporting evidence in a sample of AA women.