Population admixture plays a role in the risk of chronic conditions that are related to body composition; however, our understanding of these associations in Puerto Ricans, a population characterized by multiple ancestries, is limited. This study investigated the relationship between genetic admixture and body composition in 652 Puerto Ricans from the Boston Puerto Rican Osteoporosis Study. Genetic ancestry was estimated from 100 ancestry-informative markers. Body composition measures were obtained from dual-energy X-ray absorptiometry. Multivariable linear regression analyses examined associations between bone mineral density (BMD) of the hip and lumbar spine and percent fat mass and lean mass with genetic admixture. In Puerto Ricans living on the US mainland, European ancestry was associated with lower BMD at the trochanter (P = 0.039) and femoral neck (P = 0.01), and Native American ancestry was associated with lower BMD of the trochanter (P = 0.04). African ancestry was associated with a higher BMD at the trochanter (P = 0.004) and femoral neck (P = 0.001). Ancestry was not associated with percent fat mass or lean mass or waist circumference. Our findings are consistent with existing research demonstrating inverse associations between European and Native American ancestries and BMD and positive relationships between African ancestry and BMD. This work contributes to our understanding of the high prevalence of chronic disease experienced by this population and has implications for other ethnic minority groups, particularly those with multiple ancestries. Future research should consider interactions between ancestry and environmental factors, as this may provide individualized approaches for disease prevention.
Keywords: Aging; Dual-energy X-ray absorptiometry; Genetics; Race/ethnicity.