Exact tests for association between alleles at arbitrary numbers of loci

  • D. Zaykin
  • L. Zhivotovsky
  • B. S. Weir
Part of the Contemporary Issues in Genetics and Evolution book series (CIGE, volume 4)


Associations between allelic frequencies, within and between loci, can be tested for with an exact test. The probability of the set of multi-locus genotypes in a sample, conditional on the allelic counts, is calculated from multinomial theory under the hypothesis of no association. Alleles are then permuted and the conditional probability calculated for the permuted genotypic array. The proportion of arrays no more probable than the original sample provides the significance level for the test. An algorithm is provided for counting genotypes efficiently in the arrays, and the powers of the test presented for various kinds of association. The powers for the case when associations are generated by admixture of several populations suggest that exact tests are capable of detecting levels of association that would affect forensic calculations to a significant extent.

Key words

exact tests allelic association Hardy-Weinberg linkage disequilibrium 


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Copyright information

© Springer Science+Business Media Dordrecht 1995

Authors and Affiliations

  • D. Zaykin
    • 1
  • L. Zhivotovsky
    • 2
  • B. S. Weir
    • 1
  1. 1.Program in Statistical Genetics, Department of StatisticsNorth Carolina State UniversityRaleighUSA
  2. 2.Institute of Gene BiologyRussian Academy of SciencesMoscowRussia

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