Original Paper

Accounting for Epistasis in Linkage Analysis of General Pedigrees
Yun Ju Sung^a, Ellen M. Wijsman<sup>a-c

a</sup>Division of Medical Genetics, Department of Medicine, Departments of
^bBiostatistics and
^cDepartment of Genome Science, University of Washington, Washington, Wash., USA

Address of Corresponding Author

Hum Hered 2007;63:144-152 (DOI: 10.1159/000099186)

  Key Words

• Markov chain Monte Carlo
• Extended pedigrees
• Parametric (model-based) analysis
• Lod score
• Multi-locus

  Abstract

Complex traits are generally believed to be influenced by multiple loci. Identification of loci involved in complex traits is more difficult for interacting than for additive loci. Here we describe an extension of the program lm_twoqtl in the package MORGAN to handle two quantitative trait loci (QTLs) with gene-gene interaction. We investigate whether parametric linkage analysis that accounts for such epistasis improves prospects for linkage detection and accuracy of localization of QTLs. Through use of simulated data we show that analysis that accounts for epistasis provides higher lod scores and better localization than does analysis without epistasis. In addition, we demonstrate that the difference between lod scores in the presence vs. absence of use of an interaction model in analysis is greater in extended than in nuclear pedigrees.

Copyright © 2007 S. Karger AG, Basel

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  Author Contacts

Dr. Ellen M. Wijsman
Division of Medical Genetics, University of Washington
Box 357720
Seattle, WA 98195-7720 (USA)
Tel. +1 206 543 8987, Fax +1 206 616 1973, E-Mail wijsman@u.washington.edu

  Article Information

Published online: February 2, 2007
Number of Print Pages : 9
Number of Figures : 4, Number of Tables : 3, Number of References : 34

  Publication Details

Human Heredity (International Journal of Human and Medical Genetics)

Vol. 63, No. 2, Year 2007 (Cover Date: February 2007)

Journal Editor: Devoto, M. (Philadelphia, Pa.)
ISSN: 0001-5652 (print), 1423-0062 (Online)

For additional information: http://www.karger.com/HHE

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