Unbiased estimation of gene diversity in samples containing related individuals: Exact variance and arbitrary ploidy

Michael DeGiorgio, Ivana Jankovic, Noah A. Rosenberg

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Gene diversity, a commonly used measure of genetic variation, evaluates the proportion of heterozygous individuals expected at a locus in a population, under the assumption of Hardy-Weinberg equilibrium. When using the standard estimator of gene diversity, the inclusion of related or inbred individuals in a sample produces a downward bias. Here, we extend a recently developed estimator shown to be unbiased in a diploid autosomal sample that includes known related or inbred individuals to the general case of arbitrary ploidy. We derive an exact formula for the variance of the new estimator, H̃, and present an approximation to facilitate evaluation of the variance when each individual is related to at most one other individual in a sample. When examining samples from the human X chromosome, which represent a mixture of haploid and diploid individuals, we find that H̃ performs favorably compared to the standard estimator, both in theoretical computations of mean squared error and in data analysis. We thus propose that H̃ is a useful tool in characterizing gene diversity in samples of arbitrary ploidy that contain related or inbred individuals.

Original languageEnglish (US)
Pages (from-to)1367-1387
Number of pages21
JournalGenetics
Volume186
Issue number4
DOIs
StatePublished - Dec 1 2010

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Ploidies
Diploidy
Chromosomes, Human, X
Genes
Haploidy
Population

All Science Journal Classification (ASJC) codes

  • Genetics

Cite this

DeGiorgio, Michael ; Jankovic, Ivana ; Rosenberg, Noah A. / Unbiased estimation of gene diversity in samples containing related individuals : Exact variance and arbitrary ploidy. In: Genetics. 2010 ; Vol. 186, No. 4. pp. 1367-1387.
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Unbiased estimation of gene diversity in samples containing related individuals : Exact variance and arbitrary ploidy. / DeGiorgio, Michael; Jankovic, Ivana; Rosenberg, Noah A.

In: Genetics, Vol. 186, No. 4, 01.12.2010, p. 1367-1387.

Research output: Contribution to journalArticle

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