Article

Score test for detecting linkage to complex traits in selected samples.

Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, University of Leiden, PO Box 9604, Leiden, The Netherlands.
Genetic Epidemiology (Impact Factor: 4.02). 10/2004; 27(2):97-108. DOI: 10.1002/gepi.20012
Source: PubMed

ABSTRACT We present a unified approach to selection and linkage analysis of selected samples, for both quantitative and dichotomous complex traits. It is based on the score test for the variance attributable to the trait locus and applies to general pedigrees. The method is equivalent to regressing excess IBD sharing on a function of the traits. It is shown that when population parameters for the trait are known, such inversion does not entail any loss of information. For dichotomous traits, pairs of pedigree members of different phenotypic nature (e.g., affected sib pairs and discordant sib pairs) can easily be combined as well as populations with different trait prevalences.

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