BACKGROUND: We analyzed the shared genetic background of extensive anthropometric measurements, determining body size and morphology.

METHODS: Anthropometric measurements were taken for 15 traits from 1512 US twins at an average age of 11.7 years (Minnesota, 51% females) and for 20 traits at an average age of 14.8 years for males (N = 624) and 18.1 years for females (N = 505). Genetic twin modeling was utilized to estimate the genetic correlations between these traits.

RESULTS: In mid to late adolescence, high genetic correlations were found within height-related traits and foot length (rA = 0.58–1.00) as well as within adiposity-related traits (r A = 0.70–0.96), except for skinfold thicknesses. Genetic correlations for craniofacial measurements were smaller (r A=0.26–0.80). However, almost all traits showed some genetic correlations with other traits, most of which were at least moderate (rA > 0.30). Results from earlier assessments in early adolescence with fewer traits but a larger sample size were largely similar. Genetic correlations between the initial and follow-up assessments were high (r A = 0.68–0.95), except for craniofacial traits, which showed somewhat lower correlations (rA = 0.40–0.87).

CONCLUSIONS: Shared genetic variation plays a significant role in human body size and morphology as well as their development during adolescence.