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Mapping of complex traits by single-nucleotide polymorphisms.

L P Zhao·C Aragaki·L Hsu·F Quiaoit
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Abstract

Molecular geneticists are developing the third-generation human genome map with single-nucleotide polymorphisms (SNPs), which can be assayed via chip-based microarrays. One use of these SNP markers is the ability to locate loci that may be responsible for complex traits, via linkage/linkage-disequilibrium analysis. In this communication, we describe a semiparametric method for combined linkage/linkage-disequilibrium analysis using SNP markers. Asymptotic results are obtained for the estimated parameters, and the finite-sample properties are evaluated via a simulation study. We also applied this technique to a simulated genome-scan experiment for mapping a complex trait with two major genes. This experiment shows that separate linkage and linkage-disequilibrium analyses correctly detected the signals of both major genes; but the rates of false-positive signals seem high. When linkage and linkage-disequilibrium signals were combined, the analysis yielded much stronger and clearer signals for the presence of two major genes than did two separate analyses.

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Biosensing TechniquesChromosome MappingGenetic Diseases, InbornGenetic LinkageGenetic MarkersGenome, HumanGenotypeHumansLinkage DisequilibriumModels, GeneticNucleotidesPedigreePolymorphism, GeneticJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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L P Zhao, C Aragaki, L Hsu, F Quiaoit. 1998. Mapping of complex traits by single-nucleotide polymorphisms.. https://doi.org/10.1086/301909

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