Delphinapterus leucas skin transcriptome sequencing and assembly, and comparison between two Canadian populations
The St. Lawrence Estuary (SLE) beluga (Delphinapterus leucas) population in Canada is endangered, and endocrine disrupting contaminants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and other halogenated flame retardants (HFRs) have been identified as a threat to the recovery of this population. While targeted approaches such as quantitative reverse transcription PCR (RT-qPCR) have been widely used to assess the impacts of contaminants on marine mammals, including SLE beluga, few studies have employed transcriptomics. Here, we (1) evaluate the skin transcriptome profiles of adult male SLE beluga and adult males from a Arctic population less exposed to contaminants (Eastern Beaufort Sea; EBS) used as a reference to identify gene transcripts and biological pathways associated with blubber concentrations of organic contaminants (i.e., PCBs, PBDEs and other HFRs), and (2) assess correlations between several gene transcripts previously identified as biomarkers of organic contaminants in marine mammals and organohalogen concentrations in both populations and estimate threshold values in beluga skin for potential biological effects. Results will provide new and valuable knowledge that identify biological pathways associated with organic contaminant exposure in beluga, which may serve as predictors for higher-level health effects in at-risk populations such as SLE beluga.