On the Estimation of Heritability with Family-Based and Population-Based Samples

Table 3

Estimates of variance components in the HTK cohort. MZ and DZ twins were separated out and used to estimate correlations of MZ and DZ twins. indicates a lower bound for the proportion of variance explained by the environmental effects shared by family members.

	cor (MZ)^a	cor (DZ)^b
Height	0.970	0.832	0.694 (0.690, 0.698)
BMI	0.729	0.232	0.266 (0.061, 0.496)
	0.551	0.336	0.121 (0.070, 0.172)
TCHL	0.624	0.382	0.139 (0.093, 0.185)
HDL	0.677	0.476	0.275 (0.240, 0.310)
LDL	0.656	0.342	0.028 (−0.022, 0.078)
SBP	0.601	0.453	0.306 (0.268, 0.344)
DBP	0.646	0.585	0.524 (0.501, 0.547)

Correlation of MZ twins. ^bCorrelation of DZ twins.