Robust Inference for Variance Components Models in
Families Ascertained Through Probands: II.
Analysis of Spirometric Measures.
Beaty TH, Liang KY, Seerey S, Cohen BH
Genetic Epidemiology, 4(3):211-221 (1987)
Abstract
Three spirometric measures of pulmonary function were used to estimate genetic and
nongenetic components of variance for 781 members of 158 families ascertained through a
proband with obstructive pulmonary disease. Forced expiratory volume in 1 sec (FEV1),
forced vital capacity (FVC), and the ratio of these two (FEV1/FVC) were adjusted for age,
sex, race, smoking, and height and used in a robust approach to estimate variance
components after conditioning on the proband's observed value. The best fitting model for
both residual FEV1/FVC and FEV1 included an additive genetic component representing
25% and 9% of the variation in these two traits, respectively. In addition, there was a
significant correlation between parents in residual FEV1/FVC, and a component shared
among full sibs was statistically significant for residual FEV1. No evidence of a genetic
component for residual FVC was found in this analysis. Although these results agree with
previous reports based on other populations in showing a substantial degree of direct
genetic control over spirometric measures of pulmonary function, they also raise the
possibility of etiologic heterogeneity.
Variance component linkage analysis