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Rhodopsin gene polymorphism associated with divergent light environments in Atlantic cod.
Christophe Pampoulie1, Sigurlaug Skirnisdottir, Bastiaan Star
1Marine Research Institute, Skúlagata 4, 101, Reykjavík, Iceland, chrisp@hafro.is.
Behavior Genetics
|January 12, 2015
Summary
Atlantic cod exhibit genetic variations in their rhodopsin (RH1) gene, linked to vision and adaptation to different light environments. These RH1 gene polymorphisms correlate with population differences, suggesting a role in local adaptation.
Area of Science:
- Evolutionary Biology
- Genetics
- Marine Biology
- Vision Research
Background:
- Visual pigments, like rhodopsin (RH1), are crucial for vision in vertebrates, adapting spectral sensitivity to specific light conditions.
- RH1 mediates dim-light vision, and genetic variations (polymorphisms) in its coding region can alter spectral sensitivity.
- Such adaptations are vital for fish inhabiting diverse light environments and depths.
Purpose of the Study:
- To investigate rhodopsin (RH1) gene polymorphism in two Atlantic cod ecotypes from Icelandic waters.
- To explore the relationship between RH1 gene variations and divergent light environments influenced by foraging behavior.
- To assess the role of the visual system in the local adaptation of Atlantic cod populations.
Main Methods:
- Analysis of RH1 gene polymorphism in two distinct Atlantic cod ecotypes.
- Identification of single nucleotide polymorphisms (SNPs) within the RH1 protein coding region and the 3' untranslated region (3'-UTR).
- Comparison of identified RH1 SNPs with the known panthophysin (Pan I) polymorphism differentiating coastal and frontal cod populations.
Main Results:
- One synonymous SNP in the RH1 coding region and one in the 3'-UTR were identified.
- These RH1 polymorphisms showed strong divergence between the two studied Atlantic cod ecotypes.
- The identified RH1 SNPs were found to coincide with the panthophysin (Pan I) polymorphism.
Conclusions:
- The study identified divergent RH1 gene polymorphisms in Atlantic cod associated with different light environments.
- These findings suggest the involvement of the visual system, specifically the dim-light pigment rhodopsin, in local adaptation.
- The association of RH1 SNPs with the Pan I polymorphism highlights the genetic basis for adaptation in Atlantic cod populations.
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