Published in

Cambridge University Press, Twin Research and Human Genetics, 2(8), p. 87-94, 2005

DOI: 10.1375/twin.8.2.87

Cambridge University Press, Twin Research and Human Genetics, 2(8), p. 87-94

DOI: 10.1375/1832427053738827

Links

Tools

Export citation

Search in Google Scholar

Allele Frequencies and the r2 Measure of Linkage Disequilibrium: Impact on Design and Interpretation of Association Studies

Journal article published in 2005 by Naomi R. Wray ORCID
This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
Red circle
Postprint: archiving forbidden
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

AbstractThe design and interpretation of genetic association studies depends on the relationship between the genotyped variants and the underlying functional variant, often parameterized as the squared correlation orr2measure of linkage disequilibrium between two loci. While it has long been recognized that placing a constraint on ther2between two loci also places a constraint on the difference in frequencies between the coupled alleles, this constraint has not been quantified. Here, quantification of this severe constraint is presented. For example, forr2≥ .8, the maximum difference in allele frequency is ± .06 which occurs when one locus has allele frequency .5. Forr2≥ .8 and allele frequency at one locus of .1, the maximum difference in allele frequency at the second locus is only ± .02. The impact on the design and interpretation of association studies is discussed.