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Epigenetics and phenotypic variability: some interesting insights from birds
Laure Frésard1, Mireille Morisson, Jean-Michel Brun
1INRA, UMR444, Laboratoire de Génétique Cellulaire, Castanet-Tolosan F-31326, France.
Genetics, Selection, Evolution : GSE
|June 14, 2013
Summary
Epigenetic mechanisms, like genomic imprinting, may explain bird trait variability. Further research could enhance avian breeding by understanding environmental influences on phenotype across generations.
Area of Science:
- Avian biology
- Epigenetics
- Animal breeding
Background:
- Epigenetic mechanisms are crucial for phenotypic variability in livestock but remain understudied in birds.
- Existing knowledge primarily focuses on sex chromosome dosage compensation, neglecting other epigenetic phenomena.
Purpose of the Study:
- To review epigenetic mechanisms potentially influencing avian trait variability.
- To compare avian epigenetics with mammalian knowledge.
- To address the existence of genomic imprinting, embryonic environment effects on phenotype, and transgenerational impacts in birds.
Main Methods:
- Literature review
- Comparative analysis of avian and mammalian epigenetic data.
Main Results:
- The review highlights the limited understanding of avian epigenetics beyond sex chromosome dosage compensation.
- It identifies key research questions regarding genomic imprinting and environmental influences on avian phenotypes.
Conclusions:
- Epigenetic mechanisms may significantly contribute to avian phenotypic variability.
- Understanding these mechanisms could offer new avenues for improving avian breeding and animal performance.
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