Superfund Research Program
Mechanisms and Impacts of PCB Resistant Fish
Project Leader: Mark E. Hahn (Woods Hole Oceanographic Institution)
Co-Investigators: Sibel I. Karchner (Woods Hole Oceanographic Institution), Neelakanteswar Aluru (Woods Hole Oceanographic Institution)
Grant Number: P42ES007381
Funding Period: 1995-2020
This year, the team of Mark Hahn, Ph.D., Sibel Karchner, Ph.D., Neelakanteswar Aluru, Ph.D., and colleagues continued their research into understanding how fish in the New Bedford Harbor developed the ability to survive historically high levels of toxic polychlorinated biphenyls (PCBs) and related chemicals. By sequencing the entire genome of the sentinel killifish genome, the research team, together with colleagues around the country, were able to shed light on the changes in the genetic makeup of this model species. This genome sequence contributed to studies on factors responsible for responses to low oxygen levels and ryanodine receptors, both of which were shown to be altered in PCB-resistant killifish. The team published a review paper exploring the mechanisms and significance of rapid adaptation in fish populations exposed to Superfund chemicals and continued efforts, using cutting edge genome-editing technology, attempt to recapitulate the genomic changes driven by high level PCB exposures. These studies pinpointed changes in a gene (AIP) critical to PCB responses in the fish. An important milestone was reached when fish with mutations in AIP and two other genes linked to AIP were genetically engineered. Overall, this research has helped them to understand how natural populations of animals are affected by long-term exposure to toxic chemicals in the environment. Furthermore, the research applies innovative molecular approaches in an ecological context to understand generational, early-life exposure to Superfund chemicals. In other words, environmental chemicals can change the gene pool of exposed populations.