Variance decomposition of apolipoproteins and lipids in Danish twins

Objective: Twin studies are used extensively to decompose the variance of a trait, mainly to estimate the heritability of the trait. A second purpose of such studies is to estimate to what extent the non-genetic variance is shared or specific to individuals. To a lesser extent the twin studies have been used in bivariate or multivariate analysis to elucidate common genetic factors to two or more traits. Methods and results: In the present study the variances of traits related to lipid metabolism is decomposed in a relatively large Danish twin population, including bivariate analysis to detect possible common genetic factors of the traits. Conclusions: The heritabilities of apolipoprotein B and E, cholesterol, LDL, and high density lipoprotein (HDL) were significant in the general population, although gender-specific levels and significance were detected. Heritabilities of apolipoprotein A1, triglycerides, and very low density protein (VLDL) were only significant when the population was stratified according to gender. (c) 2006 Elsevier Ireland Ltd. All rights reserved.