Dr. Klint Kanopka and a colleague published a paper in the Proceedings of the National Academy of Sciences of the United States of America (PNAS) introducing the phenotype differences model, which can be used to estimate genetic effects using a single individual’s genotype, addressing environmental confounding in genetic research. By applying this model to the Wisconsin Longitudinal Study, they found that polygenic indices for body mass index, self-rated health, and chronic obstructive pulmonary disease significantly impact lifespan.