Growth and development of bodyweight, height and head circumference during the first two years of life: Quantitative genetic aspects

Mother-offspring and sib-sib relationships enable estimation of the heritability coefficients (or more accurately, transmissibility coefficients) and the so-called 'genetic correlation' for stature (S), weight (W) and head circumference (HC) in Israeli infants from birth to about two years of age. Heritability coefficients for S and HC show a more or less defined trend towards increase during ontogenetic development. The family resemblance in weight remains relatively constant or independent of age. The genetic correlations between each pair of the characters studied were higher than the corresponding phenotypic ones and showed an obvious tendency to decrease with age. The environmental correlations (rE) between W and S and between W and HC increase significantly with age, while for S and HC they are independent of age.