Date of Award
Great Lakes Institute for Environmental Research
Biological sciences, Common garden, Genetic architecture, Maternal effects, Outbreeding depression, Transcription, Oncorhynchus tshawytscha
CC BY-NC-ND 4.0
Chinook salmon ( Oncorhynchus tshawytscha ) life history provides an excellent opportunity to study the molecular mechanisms of selective divergence. I analyzed gene transcription in Chinook salmon that were created in a replicated North Carolina II breeding design to estimate quantitative genetic parameters that contributed to among-population variation in gene expression. Following Fischer's fundamental theorem, transcriptional variation of many genes was due to additive effects. However, a surprising number of genes exhibited non-additive genetic and maternal effects on transcription, and these effects may explain the high potential for rapid population-level evolution in salmon. Indeed, populations differed substantially in gene transcription. Pervasive non-additive gene expression raises concerns for conservation strategies that result in intraspecific hybridization. I document extensive amounts of reciprocal hybrid disagreement in gene transcription, indicative of breakdown of gene expression regulation complexes that are likely co-adapted. Anomalous hybrid gene transcription warrants caution for conservation strategies that employ mixing natural stocks.
Ouellette, Matthew J., "Transcriptional variation among populations of salmon: The genetic architecture of local adaptation" (2013). Electronic Theses and Dissertations. 4896.