- THIS ARTICLE
- Full Text
- Full Text (PDF)
-
All Versions of this Article:
genetics.107.084772v1
179/4/2027 most recent - Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Email this article to a friend
- Related articles in Genetics
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Rosenberg, N. A.
- Articles by Jakobsson, M.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Rosenberg, N. A.
- Articles by Jakobsson, M.
Originally published as Genetics Published Articles Ahead of Print on August 9, 2008.
Genetics, Vol. 179, 2027-2036, August 2008, Copyright © 2008
doi:10.1534/genetics.107.084772
The Relationship Between Homozygosity and the Frequency of the Most Frequent Allele
Noah A. Rosenberg1 and Mattias Jakobsson
Department of Human Genetics, Center for Computational Medicine and Biology, and the Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109-2218
1 Corresponding author: University of Michigan, 2017 Palmer Commons, 100 Washtenaw Ave., Ann Arbor, MI 48109-2218.
E-mail: rnoah{at}umich.edu
Homozygosity is a commonly used summary of allele-frequency distributions at polymorphic loci. Because high-frequency alleles contribute disproportionately to the homozygosity of a locus, it often occurs that most homozygotes are homozygous for the most frequent allele. To assess the relationship between homozygosity and the highest allele frequency at a locus, for a given homozygosity value, we determine the lower and upper bounds on the frequency of the most frequent allele. These bounds suggest tight constraints on the frequency of the most frequent allele as a function of homozygosity, differing by at most 
and having an average difference of 
– 
2/18 
0.1184. The close connection between homozygosity and the frequency of the most frequent allele—which we illustrate using allele frequencies from human populations—has the consequence that when one of these two quantities is known, considerable information is available about the other quantity. This relationship also explains the similar performance of statistical tests of population-genetic models that rely on homozygosity and those that rely on the frequency of the most frequent allele, and it provides a basis for understanding the utility of extended homozygosity statistics in identifying haplotypes that have been elevated to high frequency as a result of positive selection.
Related articles in Genetics:
ISSUE HIGHLIGHTS
Genetics 2008 179: NP.
 |