A latitudinal cline in the Chinook salmon (Oncorhynchus tshawytscha) Clock gene: evidence for selection on PolyQ length variants
2008

Genetic Variation in Chinook Salmon Clock Gene and Migration Timing

Sample size: 42 publication 10 minutes Evidence: high

Author Information

Author(s): O'Malley Kathleen G, Banks Michael A

Primary Institution: Oregon State University

Hypothesis

Does allelic variation at the circadian rhythm genes OtsClock1a and OtsClock1b influence migration timing in Chinook salmon populations across North America?

Conclusion

The study found that length polymorphisms in the OtsClock1b PolyQ region are associated with migration timing and vary with latitude, suggesting ecological adaptation.

Supporting Evidence

  • Eight length variants of the OtsClock1b PolyQ domain were identified among 42 Chinook salmon populations.
  • The shorter 335 bp allele increases in frequency with decreasing latitude, while the longer 359 bp allele increases in frequency at higher latitudes.
  • Run timing explains 40.9% of the overall genetic variance among populations based on OtsClock1b variation.

Takeaway

Chinook salmon have different versions of a gene that helps them know when to migrate, and these versions change depending on where they live.

Methodology

The study involved screening 42 populations of Chinook salmon for length polymorphisms in the OtsClock1a and OtsClock1b PolyQ domains and analyzing associations with migration timing and latitude.

Limitations

The study may not account for all ecological factors influencing migration timing.

Participant Demographics

Chinook salmon populations from North America, including regions from California to Alaska.

Statistical Information

P-Value

<0.0001

Statistical Significance

p<0.0001

Digital Object Identifier (DOI)

10.1098/rspb.2008.0524

Want to read the original?

Access the complete publication on the publisher's website

View Original Publication