PCBs are associated with altered gene transcript profiles in arctic Beluga Whales (Delphinapterus leucas).
High trophic level arctic beluga whales (Delphinapterus leucas) are exposed to persistent organic pollutants (POP) originating primarily from southern latitudes. We collected samples from 43 male beluga harvested by Inuvialuit hunters (2008-2010) in the Beaufort Sea to evaluate the effects of POPs on the levels of 13 health-related gene transcripts using quantitative real-time polymerase chain reaction. Consistent with their role in detoxification, the aryl hydrocarbon receptor (Ahr) (r(2) = 0.18, p = 0.045 for 2008 and 2009) and cytochrome P450 1A1 (Cyp1a1) (r(2) = 0.20, p < 0.001 for 2008 and 2009; r(2) = 0.43, p = 0.049 for 2010) transcripts were positively correlated with polychlorinated biphenyls (PCBs), the dominant POP in beluga. Principal Components Analysis distinguished between these two toxicology genes and 11 other genes primarily involved in growth, metabolism, and development. Factor 1 explained 56% of gene profiles, with these latter 11 gene transcripts displaying greater abundance in years coinciding with periods of low sea ice extent (2008 and 2010). δ(13)C results suggested a shift in feeding ecology and/or change in condition of these ice edge-associated beluga whales during these two years. While this provides insight into the legacy of PCBs in a remote environment, the possible impacts of a changing ice climate on the health of beluga underscores the need for long-term studies.
School of Earth and Ocean Sciences, University of Victoria , Victoria, British Columbia V8W 2Y2, Canada.
Marie
M
Noël
Lisa L
LL
Loseto
Caren C
CC
Helbing
Nik
N
Veldhoen
Neil J
NJ
Dangerfield
Peter S
PS
Ross
D000273:Adipose Tissue / Q000737:chemistry; D000818:Animals; D001110:Arctic Regions; D050643:Beluga Whale / Q000235:genetics*; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics; D004784:Environmental Monitoring; D055768:Halogenated Diphenyl Ethers / Q000032:analysis; D008099:Liver / Q000737:chemistry; D008297:Male; D008628:Mercury / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D012333:RNA, Messenger / Q000032:analysis; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics; D059467:Transcriptome; D014874:Water Pollutants, Chemical / Q000032:analysis*
D055768:Halogenated Diphenyl Ethers; D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls; D019363:Cytochrome P-450 CYP1A1; D008628:Mercury