Abstract
Evolutionary biologists have long sought a way to determine whether a phenotypic difference between two taxa was caused by natural selection or random genetic drift. Here I argue that data from quantitative trait locus (QTL) analyses can be used to test the null hypothesis of neutral phenotypic evolution. I propose a sign test that compares the observed number of plus and minus alleles in the "high line" with that expected under neutrality, conditioning on the known phenotypic difference between the taxa. Rejection of the null hypothesis implies a role for directional natural selection. This test is applicable to any character in any organism in which QTL analysis can be performed.
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Selected References
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- Coyne J. A. Genetics of a difference in male cuticular hydrocarbons between two sibling species, Drosophila simulans and D. sechellia. Genetics. 1996 Aug;143(4):1689–1698. doi: 10.1093/genetics/143.4.1689. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Edwards M. D., Stuber C. W., Wendel J. F. Molecular-marker-facilitated investigations of quantitative-trait loci in maize. I. Numbers, genomic distribution and types of gene action. Genetics. 1987 May;116(1):113–125. doi: 10.1093/genetics/116.1.113. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laurie C. C., True J. R., Liu J., Mercer J. M. An introgression analysis of quantitative trait loci that contribute to a morphological difference between Drosophila simulans and D. mauritiana. Genetics. 1997 Feb;145(2):339–348. doi: 10.1093/genetics/145.2.339. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Paterson A. H., Damon S., Hewitt J. D., Zamir D., Rabinowitch H. D., Lincoln S. E., Lander E. S., Tanksley S. D. Mendelian factors underlying quantitative traits in tomato: comparison across species, generations, and environments. Genetics. 1991 Jan;127(1):181–197. doi: 10.1093/genetics/127.1.181. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zeng Z. B. Correcting the bias of Wright's estimates of the number of genes affecting a quantitative character: a further improved method. Genetics. 1992 Aug;131(4):987–1001. doi: 10.1093/genetics/131.4.987. [DOI] [PMC free article] [PubMed] [Google Scholar]