title: The effect of pedigree complexity on quantitative trait linkage analysis.
abstract: Due to the computational difficulties of performing linkage analysis on large complex pedigrees, most investigators resort to simplifying such pedigrees by some ad hoc strategy. In this paper, we suggest an analytical method to compare the power of various pedigree simplification schemes by using the asymptotic distribution of the likelihood-ratio statistic. We applied the method to the large Hutterine pedigree. Our results indicate that the breaking and reduction of inbreeding loops can greatly diminish the power to localize quantitative trait loci. We also present an efficient Monte Carlo method for estimating identity-by-descent allele sharing in large complex pedigrees. This method is used to facilitate a linkage analysis of serum IgE levels in the Hutterites without simplifying the pedigree.
authors.affiliation: Department of Genetics, Southwest Foundation for Biomedical Research, 7620 NW Loop 410, P.O. Box 760549, San Antonio, TX 78245-0549, USA.
authors.forename: T D
authors.initials: TD
authors.lastname: Dyer
authors.forename: J
authors.initials: J
authors.lastname: Blangero
authors.forename: J T
authors.initials: JT
authors.lastname: Williams
authors.forename: H H
authors.initials: HH
authors.lastname: Göring
authors.forename: M C
authors.initials: MC
authors.lastname: Mahaney
mesh_terms: D000328:Adult; D001249:Asthma / Q000453:epidemiology / Q000235:genetics*; D002648:Child; D002874:Chromosome Mapping / Q000706:statistics & numerical data*; D003241:Consanguinity; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008126:Lod Score; D008297:Male; D008957:Models, Genetic; D010375:Pedigree; D019655:Quantitative Trait, Heritable; D013023:South Dakota