Segregation analysis of apolipoprotein A1 levels in families of adolescents: A community-based study in Taiwan

Abstract

Background: Apolipoprotein (Apo) Al is a protective factor for cardiovascular events. This study aimed to perform complex segregation analyses of Apo Al levels in families of adolescents systematically ascertained from the junior high school students in a rural community. Both siblings and parents of the adolescent probands were recruited for the study. Apo Al concentrations were measured by turbidimetric immunoassay methods. After adjustment for gender, age, body mass index, smoking and drinking status, residual values of Apo Al were subjected to subsequent analyses. Results: Significant mother-father and parent-offspring correlations were found. Commingling analyses indicated that a four-component distribution model was needed to account for the Apo Al variation. Segregation analysis using regressive models revealed that the best-fit model of Apo Al was a model of environmental effect plus familial correlation (heritability = 23.9%), in which a significant mother-father correlation existed. Models containing major gene effect could be rejected. Conclusion: These results suggest that variations of Apo Al levels in the normal range, especially during adolescence, are likely to be influenced by multiple factors without significant contribution from major genes. © 2006 Chien et al; license BioMed Central Ltd.