title: Sequential genotyping within TDT families.
abstract: We demonstrate that, given a limited amount of genotyping resources, the power of a TDT study can be increased substantially by genotyping within families sequentially. By sequential genotyping we mean that one parent in a family should be typed and then the decision on whether to continue genotyping the family is based on this parent's genotype. If it is decided to continue genotyping then a further decision is made about whether to genotype the offspring once the second parent has been genotyped. We show that, for a given power, reductions in sample size of over 80% are possible, even for the most robust selection strategies. We discuss the practical application of such sequential genotyping and illustrate its potential using a real data set.
authors.affiliation: Division of Genomic Medicine, University of Sheffield, Royal Hallamshire Hospital, Sheffield S10 2JF, UK. mark.iles@meb.ki.se
authors.forename: Mark M
authors.initials: MM
authors.lastname: Iles
authors.forename: Chris
authors.initials: C
authors.lastname: Cannings
mesh_terms: D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics; D005260:Female; D030342:Genetic Diseases, Inborn / Q000235:genetics*; D005838:Genotype; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D008957:Models, Genetic; D010290:Parents