Implementing a unified approach to family-based tests of association

We describe a broad class of family-based association tests that are adjust ed for admixture; use either dichotomous or measured phenotypes; accommodat e phenotype-unknown subjects; use nuclear families, sibships or a combinati on of the two, permit multiple nuclear families from a single pedigree; inc orporate di- or multi-allelic marker data; allow additive, dominant or rece ssive 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 tr ait. The distribution of the statistic is computed using the appropriate co nditional distribution of offspring genotypes that adjusts for admixture. G enet. Epidemiol. 19(Suppl 1):S36-S42, 2000. (C) 2000 Wiley-Liss, Inc.