Genetic and environmental contributions to serum retinol and alpha-tocopherol concentrations: the Stanislas Family Study

BACKGROUND: Although numerous environmental factors are documented to influence serum retinol and alpha-tocopherol concentrations, little is known about the genetic versus the environmental contributions to variations in these traits. OBJECTIVE: The aim of this study was to estimate additive genetic heritability and household effects for serum retinol and alpha-tocopherol concentrations in a variance component analysis. DESIGN: In a sample of 387 French families, information on serum retinol and alpha-tocopherol concentrations, usual dietary intake, lifestyle, and serum lipid profiles and related polymorphisms (apolipoprotein E, apolipoprotein C-III, apolipoprotein B, cholesteryl ester transfer protein, and lipoprotein lipase) was obtained. RESULTS: For serum retinol--after adjustment for sex, age, body mass index, alcohol consumption, oral contraceptive use, and serum albumin, triacylglycerol, and apolipoprotein A-I concentrations--additive genetic effects and shared common environment contributed 30.5% and 14.2% of the total variance, respectively. For serum alpha-tocopherol, approximately 22.1% of the total variance was due to the additive effects of genes and 18.7% to those of household environment, after adjustment for the covariates sex, age, vitamin E intake, oral contraceptive use, and cholesterol, triacylglycerol, and apolipoprotein A-I concentrations. For both vitamins, the influence of measured polymorphisms was not significant. Moreover, heritability and household effect estimates were not significantly different between the 4 classes of relatives and did not vary significantly when families shared more meals at home. CONCLUSIONS: The results show that serum retinol and alpha-tocopherol concentrations are under genetic control in healthy families.