Behavior Genetic Modeling of Menarche in U.S. Females

Abstract

Most previous research has been logically unable to disentangle the genetic and environmental influences on age at menarche. We present data on 1338 kinship pairs from the National Longitudinal Survey of Youth in a behavior genetic analysis, partitioning variability in menarcheal age into genetic and environmental sources. About half the variability in menarcheal age was related to genetic influences, h(2) = .54, and almost half to nonshared environmental influences plus error. No influence of the shared environment was found. Motivated by the evolutionary theory of Belsky, Steinberg, and Draper, the influence of family composition / stability was tested as a nonshared environmental influence. In line with previous findings, father absence was associated with a younger age at menarche. Residing with two parents under extreme living conditions may delay age at menarche. No association of family size, birth order, personality, income, or parental education with age at menarche was found.