rs7965399

This study investigated the association between common genetic variation in IGF1, IGFBP1, and IGFBP3 genes and mammographic density in 819 women from the Multiethnic Cohort. Only weak evidence was found for associations: rs35767 (IGF1, p=0.03) was associated with 3.2% lower mammographic density, rs35539615 (IGFBP1, p=0.05) with higher density, and rs2453839 (IGFBP3, p=0.01) with lower density. Ethnicity significantly modified the associations for IGFBP3 variants.

This association study examined the IGF1 promoter SNP rs35767 (-C1245T) in 2,999 elderly adults (ages 70-79) from the Health ABC cohort and 483 younger adults (mean age 24.6) from the FMS cohort. The CC genotype was associated with increased body fat (2-3% higher in white women, P < 0.05) and decreased lean mass/muscle mass (3% lower in black women, P < 0.05) in elderly participants, but associations were much weaker in younger subjects. Associations were also found with reduced muscle strength in white women and lower bone mineral density in black women.

A population-based case-control study of 473 African-American men (131 prostate cancer cases, 342 controls) examined SNP associations in six genes involved in androgen and IGF-1 pathways. Significant associations were found between prostate cancer and CYP17 SNPs rs6163, rs6162, and rs743572, with heterozygotes showing decreased risk (P=0.0014, 0.0018, 0.0028). Suggestive evidence for association was found between IGF-1 SNP rs5742657 and prostate cancer (P=0.058 genotype; P=0.02 allelic test). No significant associations were observed for SNPs in CYP3A4, CYP19A1, SRD5A2, or IGFBP-3 genes.