Multifactorial Genetic Models for Quantitative Traits in Humans
Boyle CR, Elston RC
Biometrics, 35(1):55-68 (1990)
Abstract
Quantitative traits measured in human families can be analyzed to partition the total
population variance into genetic and environmental components, or to elucidate the genetic
mechanism involved. We review the estimation of variance components directly from
human pedigree data, or in the form of path coefficients from correlations between pairs of
relatives. To elucidate genetic mechanisms, a mixed model that allows for segregation at a
major locus, a polygenic effect and a sibling environmental correlation is described for
nuclear families. In each case appropriate likelihoods are derived as a basis, using
numerical maximum likelihood methods, for parameter estimation and hypothesis testing.
A general model is then described that allows for several familial sources of environmental
variation, assortative mating, and both major gene and polygenic effects; and an algorithm
for calculating the likelihood of a pedigree under this model is indicated. Finally, some of
the remaining problems in this area of biometric analysis are pointed out.
Variance component linkage analysis