Forward Genomics of a Complex Trait: Mammalian Basal Metabolic Rate

Author: Caleigh    Charlebois

Major: Zoology

Graduation Year: 2021

Thesis Advisor: Danielle Levesque

Description of Publication: The significance and nature of basal metabolic rate, a metabolic parameter recorded under specific laboratory conditions, are contested among biologists. Although it was most likely important in the evolution of endothermy in mammals and is associated with many other traits inter-and intra-specifically, the specifics of its heritability and its genetic determinants are largely unknown. Two bioinformatics pipelines are available which can associate traits with their genetic correlates given only whole genomes and phenotypes for each animal. However, extant pipelines were created with binary traits in mind. This leaves a void in our ability to associate continuous traits such as basal metabolic rate with genetic regions that influence them. To fill this gap, I developed a technique to augment the existing forward genomics pipeline developed by Hiller et al. (2012) by repeatedly analyzing a continuous trait converted to a binary trait via increasing thresholds. The results of my analysis identified a list of genes that have changed more from a reconstructed ancestral state in high BMR than in low BMR mammals. However, the list of genes did not appear to be enriched for genes associated with any biological process, function, or component clearly related to metabolism. Applying these analyses to other continuous traits could provide context for whether this result is unique to BMR, which could make a statement on its lack of straightforward genetic underpinnings, or is a result of the limitations of the forward genomics pipeline.

Location of Publication:

URL to Thesis: https://digitalcommons.library.umaine.edu/honors/653/