Transmission-disequilibrium tests for quantitative traits.

摘要: Abstract The transmission-disequilibrium test (TDT) of Spielman et al. is a family-based linkage-disequilibrium that offers powerful way to for linkage between alleles and phenotypes either causal (i.e., the marker locus disease/trait allele) or due disequilibrium. The TDT equivalent randomized experiment and, therefore, resistant confounding. When extremely close disease itself, tests such as can be far more than conventional tests. To date, most other association have been applied only dichotomous traits. This paper develops five TDT-type use with quantitative These accommodate unselected sampling based on selection phenotypically extreme offspring. Power calculations are provided show that, when candidate gene available (1) these at least an order magnitude efficient two common sib-pair linkage; (2) results in substantial increases power; (3) if 20% phenotypic distribution selectively sampled, across wide variety plausible genetic models, quantitative-trait loci explaining little 5% variation detected .0001 alpha level <300 observations.