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PubMed · 9554552

Genotypic relative risks under ordered restriction.

M N Chiano·D G Clayton
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Abstract

In mapping diseases of complex aetiology, conventional linkage approaches narrow the location of the disease susceptibility locus to quite a large region so that candidate gene association studies are then necessary to further isolate these genes. However, even in the simplest scenario where the candidate locus is bi-allelic, two statistical tests with various correcting factors have been proposed: a chi-square 1 df test (counting chromosomes) which may be slightly conservative and a 2 df chi-square test (counting genotypes) which may lack power because of the extra degree of freedom. This paper introduces a better and more powerful alternative which turns out to be a compromise between the two existing statistical tests. The asymptotic distribution of this test statistic is determined and the efficacy of the 3 tests are compared under different genetic models by simulation.

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Breast NeoplasmsCase-Control StudiesComputer SimulationFemaleGenetic Predisposition to DiseaseGenotypeHumansLikelihood FunctionsModels, GeneticRisk AssessmentStatistics as TopicJournal ArticleResearch Support, Non-U.S. Gov't

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M N Chiano, D G Clayton. 1998. Genotypic relative risks under ordered restriction.. https://doi.org/10.1002/(sici)1098-2272(1998)15%3A2%3C135%3A%3Aaid-gepi3%3E3.0.co%3B2-5

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