title: Implementing a unified approach to family-based tests of association.
abstract: We describe a broad class of family-based association tests that are adjusted for admixture; use either dichotomous or measured phenotypes; accommodate phenotype-unknown subjects; use nuclear families, sibships or a combination of the two, permit multiple nuclear families from a single pedigree; incorporate di- or multi-allelic marker data; allow additive, dominant or recessive models; and permit adjustment for covariates and gene-by-environment interactions. The test statistic is basically the covariance between a user-specified function of the genotype and a user-specified function of the trait. The distribution of the statistic is computed using the appropriate conditional distribution of offspring genotypes that adjusts for admixture.
authors.affiliation: Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts 02115, USA. laird@biostat.harvard.edu
authors.forename: N M
authors.initials: NM
authors.lastname: Laird
authors.forename: S
authors.initials: S
authors.lastname: Horvath
authors.forename: X
authors.initials: X
authors.lastname: Xu
mesh_terms: D005838:Genotype; D006801:Humans; D008957:Models, Genetic; D010641:Phenotype; D012984:Software; D013223:Statistics as Topic