Associating physiological functions with genomic variability in hibernating bats

Abstract

The challenges of surviving periods of increased physiological stress elicit selective pressures that drive adaptations to overcome hardships. Bats in the Palearctic region survive winter in hibernation. We sampled single nucleotide polymorphisms (SNPs) in hibernating Myotis myotis bats using double-digest restriction site-associated DNA sequencing and we associated the genomic variability with the observed phenotypes reflecting hibernation site preference, body condition and bat health during hibernation. We did not observe genotype associations between the detrended body condition index, representing fat reserves, and functional genes involved in fat metabolism. Bat body surface temperature, reflecting roost selection, or roost warmth relative to the climate at the site did not show any associations with the sampled genotypes. We found SNPs with associations to macroclimatic variables, characterising the hibernaculum, and blood biochemistry, related to health of the bat. The genes in proximity of the associated SNPs were involved in metabolism, immune response and signal transduction, including chaperones, apoptosis and autophagy regulators and immune signalling molecules. The genetic adaptations included adaptation to tissue repair and protection against tissue damage.