1701-P: Genome-Wide Association Study Identifies Novel Potential Associations with Birth Weight in a Southwestern American Indian Population

Epidemiologic studies in many populations have shown that birth weight is associated with risk of type 2 diabetes (T2D) in adulthood. In a Southwestern American Indian population, lower and higher birth weight groups are at higher risk for T2D than those with normal birth weight. We performed a genome-wide association study (GWAS) of birth weight in 3700 Southwestern American Indians (2037 female; 1663 male). 496,190 SNPs (allele frequency>1%) were directly genotyped using an Axiom array designed to capture common variation in this community (Affymetrix; Santa Clara, CA). Birth weight was ascertained from Arizona state and medical records. T2D was determined according to American Diabetes Association criteria at a research exam or during clinical care. Birth weight data were normalized separately by sex and analyzed for genetic associations using a mixed model (SOLAR-Eclipse; Catonsville, MD) accounting for genetic relationships (based on genetic markers among all pairs of individuals) and adjusted for birth year and the 1st 5 genetic principal components. We identified 41 variants suggestively associated (p 5 of the 41 variants are also nominally associated with T2D (p Disclosure L.E. Wedekind: None. W. Hsueh: None. S. Kobes: None. M.T. Olaiya: None. W.C. Knowler: None. L.J. Baier: None. R.L. Hanson: None.