A twin study of heritability of plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) mass and activity
Received 27 May 2008; received in revised form 1 August 2008; accepted 1 August 2008. published online 29 December 2008.
Abstract
Objective
We investigated heritability of plasma levels (mass) and activity of lipoprotein-associated phospholipase A2 (Lp-PLA2).
Materials and methods
In 54 healthy twins pairs we estimated genetic variance and heritability of Lp-PLA2 mass and activity using maximum likelihood and least squares methods. We estimated intra-class correlation (ICC) and proportion of additive genetic variance from a model comprising additive genetic influence (A), environmental effect common to cotwins (C) and individually unique environmental (E) influence (ACE) model.
Results
Twenty-six twin pairs were monozygotic (MZ) and 28 dizygotic (DZ). The Lp-PLA2 mass and activity showed a significant correlation (r=0.87, p<0.001) and the mean values were similar in MZ and DZ. ICC estimates of heritability for Lp-PLA2 were 0.27 (mass) and 0.28 (activity); ACE model-based estimates of heritability were 0.37 (mass) and 0.54 (activity). Heritability estimates were not significant for Lp-PLA2 mass, but significant for Lp-PLA2 activity.
Conclusions
These results suggest heritability for activity, but not for mass, in healthy Caucasians.
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