Estimates of the heritability of serum lipoprotein and lipid concentrations

Heritability (h2) of a serum lipid or a serum lipoprotein concentration is the proportion of variability in that concentration, among individuals, which is associated with heredity. We derive a familiar formula for estimating heritability (h2) from a simple linear model for inheritance. The formula was implied by Fisher (1918) and by Wright (1921); it was derived from a consideration of variances by Jensen (1967), and from a consideration of path coefficients by Rao et al. (1974). The estimate of heritability (ĥ2) is ĥ2 = 2(rMZ - rDZ) for twin studies, where rMZ and rDZ are the sample intraclass correlation coefficients among monozygous and dizygous twins, respectively. We calculate ĥ2 for some published twin data (Heiberg 1974) on serum lipoprotein and serum lipid concentrations.