title: Combining the case-control methodology with the small size transmission/disequilibrium test for multiallelic markers.
abstract: Case-control studies compare marker-allele distributions in affected and unaffected individuals, and significant results may be due to linkage but can also simply reflect population structure. To test for linkage after obtaining a significant case-control finding, within-family analysis can be performed. In a transmission/disequilibrium test (TDT), genotypes of cases are compared to those of their parents to explore whether a specific allele, or marker, at a locus of interest is transmitted to a greater degree than Mendelian inheritance would warrant. For multiallelic markers, several authors have proposed extensions to the TDT. In this article, we propose a TDT test, utilizing the available information of a case-control study in the grouping of alleles for multiallelic markers, and thereby increase the statistical power of a TDT test with a small sample size.
authors.affiliation: Department of Statistics and Actuarial Science, The University of Hong Kong, Hong Kong, China. Elisabeth.Flori@chru-strasbourg.fr
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Wing K
authors.initials: WK
authors.lastname: Fung
mesh_terms: D016022:Case-Control Studies; D002874:Chromosome Mapping; D003198:Computer Simulation; D005787:Gene Frequency; D005819:Genetic Markers; D005838:Genotype; D040941:Heredity; D006801:Humans; D015810:Linkage Disequilibrium; D008957:Models, Genetic
chemical_list: D005819:Genetic Markers