title: Digit ratio (2D:4D) and handgrip strength in subjects of Han ethnicity: impact of sex and age.
abstract: The ratio of the length of the second finger to the fourth finger (2D:4D) is considered to be a putative proxy of prenatal exposure to testosterone, and has been increasingly used as a promising tool to evaluate the impact of prenatal androgenization in humans in such traits as physical performance. In this study, for the first time, we present 2D:4D data on adult participants of Han ethnicity. We consider the sexual dimorphism of 2D:4D and handgrip strength, and also report the relationship between 2D:4D and handgrip strength of males and females. The sample consisted of 54 males and 55 females recruited from a remote village in the Qinling Mountains, China. We found sexual dimorphism of both 2D:4D and handgrip strength, i.e., males had lower 2D:4D and right-left 2D:4D than females and greater handgrip strength than females. There was a sex-specific correlation between 2D:4D and handgrip strength, i.e., 2D:4D in the right hand was negatively correlated with handgrip strength in males but not in females. This relationship may be driven by sexual selection operating on fetal programming.
authors.affiliation: Tianjin Key Laboratory of Cyto-Genetical and Molecular Regulation, College of Life Sciences, Tianjin Normal University, Tianjin, China. dpzhao@yahoo.cn
authors.forename: Dapeng
authors.initials: D
authors.lastname: Zhao
authors.forename: Baoguo
authors.initials: B
authors.lastname: Li
authors.forename: Keli
authors.initials: K
authors.lastname: Yu
authors.forename: Lianbin
authors.initials: L
authors.lastname: Zheng
mesh_terms: D000328:Adult; D000367:Age Factors; D002681:China; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D005385:Fingers / Q000033:anatomy & histology*; D018737:Hand Strength; D006801:Humans; D008297:Male; D008875:Middle Aged; D012727:Sex Characteristics; D018709:Statistics, Nonparametric