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First evidence of deviation from Mendelian proportions in a conservation programme
Catherine E Grueber1,2, Katherine A Farquharson1, Belinda R Wright1
1Faculty of Science, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia.
Molecular Ecology
|May 29, 2021
Summary
Conservation breeding programs may disrupt classic Mendelian inheritance due to early viability selection. This study found deviations from expected genetic proportions in endangered Tasmanian devils, impacting conservation genetics.
Area of Science:
- Conservation Genetics
- Population Genetics
- Evolutionary Biology
Background:
- Mendelian inheritance is fundamental to population genetics and animal breeding.
- Conservation breeding programs aim to maintain genetic diversity but may inadvertently introduce selection.
- The Tasmanian devil, an endangered marsupial, presents a unique model for studying evolutionary processes in managed populations.
Purpose of the Study:
- To investigate potential deviations from Mendelian inheritance in a captive Tasmanian devil metapopulation.
- To determine if early viability selection occurs in conservation breeding programs, impacting genetic proportions.
- To explore the influence of environmental conditions and management intensity on genetic patterns.
Main Methods:
- Analysis of 140 sire-dam-offspring triads in a captive Tasmanian devil population.
- Genotyping of 123 single nucleotide polymorphisms (SNPs) to compare observed offspring genotypes with Mendelian expectations.
- Statistical comparison of observed genotypes against neutral expectations to detect deviations.
Main Results:
- Observed offspring heterozygosity was lower than predicted by Mendelian inheritance.
- Subtle genetic patterns varied across different management intensities, from zoo-like to semi-wild environments.
- Evidence suggests maternal genotype influences litter size, potentially due to pre- or early-natal offspring mortality.
Conclusions:
- Deviations from Mendelian inheritance can occur in conservation programs, even with careful management.
- Early viability selection, potentially driven by maternal factors or environmental conditions, may impact genetic outcomes.
- Findings highlight the need to consider non-Mendelian factors in conservation breeding strategies for endangered species.
Keywords:
Tasmanian devil Sarcophilus harrisiiadaptationcandidate-gene resequencingheterosispedigreesreproductive successMore Related Videos
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