A Variance Components/Major Locus Likelihood Approximation
on Quantitative Data
Hasstedt SJ
Department of Human Genetics, University of Utah, Salt Lake City 84112.
Genetic Epidemiology, 8(2):113-125 (1991)
Abstract
The variance components/major locus model encompasses a major locus, a polygenic
component, and shared environmental effects. The model attributes familial correlations to
polygenic and shared environmental effects when testing for major locus inheritance or
accounts for the major locus when estimating variance components. Because exact
computation of the likelihood of the variance components/major locus model on quantitative
data requires excessive computer time, I developed an approximation. The approximation
retained the general shape of the likelihood surface. Accuracy of the approximation did not vary
consistently with allele frequency or the size of the major locus effect.
Variance component linkage analysis