WEN-CHUNG LEE2020-11-192020-11-1920030003-4800https://www.scopus.com/inward/record.uri?eid=2-s2.0-0141924144&doi=10.1046%2fj.1469-1809.2003.00018.x&partnerID=40&md5=69a2ad3819d8d4ca47b759f16fa96fa0https://scholars.lib.ntu.edu.tw/handle/123456789/521901A positive result for a transmission/disequilibrium test (TDT) can occur for two reasons: a) the allele itself is a cause of disease predisposition (direct effect); or b) the allele is in linkage disequilibrium with a disease-causing gene (indirect effect). A test was proposed based on affected sibling pairs (ASPs) to distinguish between the two. Simulation showed that the test has the correct type I error rate and favourable power (power >50% for 50 ASPs; >75% for 100 ASPs; >85% for 150 ASPs). Making this distinction is important for setting the direction for subsequent studies following a positive TDT result. ? University College London 2003.English[SDGs]SDG3allele; analytical error; article; autosomal dominant inheritance; autosomal recessive inheritance; computer simulation; controlled study; disease predisposition; disease transmission; gene linkage disequilibrium; genetic model; genetic predisposition; genetic susceptibility; genotype; human; mathematical computing; priority journal; sibling; family health; female; gene frequency; genetic predisposition; heterozygote; male; methodology; statistical model; statistics; Alleles; Family Health; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Heterozygote; Humans; Linkage Disequilibrium; Male; Models, Statistical; Statisticsjournal article10.1046/j.1469-1809.2003.00018.x126756932-s2.0-0141924144