Genetic Factors and Adult Mortality

Abstract

This chapter deals with the evidence for familial clustering of adult mortality risk and lifespan, including sections on heritability and twin and adoption studies and how these studies shed light on the underlying genetic and environmental causes. The chapter contains special sections on the influence of genetic factors on both early adult mortality and exceptionally long survival. The few specific common genetic variants with well-documented influence on adult survival are also covered. The authors conclude that about a quarter of the variance in adult lifespan in contemporary western population can be explained by genetic factors, and that the influence is likely to be larger for exceptionally long survival and generally of little importance for early adult death. The last section of the chapter describes how adult mortality studies among relatives are a powerful tool to disentangle causal effect from selection processes in studies of both social and biological mortality risk factors. Genetic studies of adult mortality and studies of mortality patterns among relatives illuminate the causes for differences in adult mortality risks among individuals in a given population at a given time.