Distribution of model-based multipoint heterogeneity lod scores

Department of Clinical Sciences, McDermott Center of Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
Genetic Epidemiology (Impact Factor: 2.95). 12/2010; 34(8):912-6. DOI: 10.1002/gepi.20535
Source: PubMed

ABSTRACT The distribution of two-point heterogeneity lod scores (HLOD) has been intensively investigated because the conventional χ(2) approximation to the likelihood ratio test is not directly applicable. However, there was no study investigating th e distribution of the multipoint HLOD despite its wide application. Here we want to point out that, compared with the two-point HLOD, the multipoint HLOD essentially tests for homogeneity given linkage and follows a relatively simple limiting distribution ½χ²₀+ ½χ²₁, which can be obtained by established statistical theory. We further examine the theoretical result by simulation studies.

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