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Updated: Aug 3, 2026
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
Relationship between heterozygosity and asymmetry: a test across the distribution range
S Kark1, U N Safriel, C Tabarroni
1Department of Biological Sciences, Stanford University, Stanford, CA 94305-5020, USA. salit@stanford.edu
Heredity
|June 22, 2001
Summary
Developmental stability, measured by bilateral asymmetry, is not linked to genetic diversity (heterozygosity) in chukar partridges. Asymmetry increased towards range edges, while heterozygosity peaked in the ecotone, suggesting asymmetry reflects environmental, not genetic, stress.
Area of Science:
- Evolutionary biology
- Developmental biology
- Genetics
Background:
- The relationship between genetic diversity and developmental stability, indicated by bilateral asymmetry, has been a long-standing debate.
- A key theory posits that greater genetic diversity (heterozygosity) enhances developmental stability, leading to reduced asymmetry.
Purpose of the Study:
- To investigate the correlation between heterozygosity and bilateral asymmetry at both population and individual levels.
- To examine if these patterns vary across a species' distribution range and in relation to environmental stress.
Main Methods:
- Assessed heterozygosity at 26 loci and third toe length asymmetry in 11 chukar partridge populations across an Israeli climatic gradient.
- Analyzed genetic diversity using observed and expected heterozygosity.
Main Results:
- No association was found between heterozygosity and asymmetry at population or individual levels.
- Heterozygosity exhibited a hump-shaped distribution, peaking at the ecotone.
- Asymmetry monotonically increased towards the periphery of the species' range.
Conclusions:
- Bilateral asymmetry may not be a reliable indicator of genetic stress.
- Asymmetry could potentially serve as a metric for environmental stress changes across populations.
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