Genetic analysis of serum lipid levels and blood pressure in a large kindred

Abstract
A 267‐member Caucasian kindred with a high incidence of cardiovascular disease, originally from Evans County, Georgia, was chosen for genetic analysis of serum lipid levels and blood pressure. Total serum cholesterol, triglycerides, high density lipoprotein cholesterol (HDL), and systolic and diastolic blood pressures were natural logarithm transformed and then adjusted for significant age, sex, and behavioral trait effects. Major gene pedigree analysis was used to estimate genetic parameters and to test hypotheses about the mode of transmission of each trait. Multivariate methods were also used to estimate linear combinations of the variables that best fit genetic models.The data were consistent with a major gene segregating for high levels of triglycerides in this kindred. However, dominant and recessive hypotheses could not be distinguished. Although diastolic blood pressure fit a mixture of two distributions significantly better than a single normal, major gene hypotheses could be rejected while the no‐transmission hypothesis could not. There was no evidence of a major gene effect on cholesterol, HDL, systolic blood pressure, or any of the hypothetical traits represented by linear functions of the physical‐lipid traits.