Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A Genetic Mutation Allows Hudson River Fish to Adapt to PCBs

18.02.2011
A research group led by a New York University School of Medicine scientist discovered a genetic variant that allows a fish in the Hudson River to live in waters heavily polluted by PCBs.

In a study published in the February 18, 2011, online issue of Science, they report that a population of Hudson River fish apparently evolved rapidly in response to the toxic chemicals, which were first introduced in 1929, and were banned fifty years later. PCBs, or polychlorinated biphenyls, were used in hundreds of industrial and commercial applications, especially as electrical insulators.

“We’ve found evolutionary change going on very quickly due to toxic exposure, and just one gene is responsible for it,” says Isaac Wirgin, a population geneticist, associate professor of environmental medicine at NYU School of Medicine, and the study’s lead investigator. “There are not many examples of this in the scientific literature."

General Electric released approximately 1.3 million pounds of PCBs into the Hudson River from 1947 to 1976. The Atlantic tomcod, Microgadus tomcod, is a common bottom-feeding fish in the Hudson that is not usually eaten by humans. The fish, which typically reaches a length of 10 inches, had long been known to survive exposure to PCBs, and levels of the chemical in its liver are among the highest reported in nature. However, scientists did not understand the biological mechanism that allowed the tomcod to survive chemical exposures that kill most other fishes.

Dr. Wirgin and scientists at NOAA Fisheries Service in New Jersey and the Woods Hole Oceanographic Institution in Massachusetts spent four years capturing tomcod from contaminated and relatively clean areas of the Hudson River during the winter months, when tomcod spawn in the river. The fish were screened for genetic variants in a gene encoding a protein known to regulate the toxic effects of PCBs, which is called the aryl hydrocarbon receptor2, or AHR2. This gene also is involved in mediating the effects of other halogenated hydrocarbon compounds, a group that includes PCBs.

Slight alterations—the deletion of only six base pairs in DNA of the AHR2 gene—appear to protect tomcod from PCBs, according to the study. Normally, when unaltered AHR2 binds to PCBs, it triggers a cascade of reactions that transmit the toxic effects of the compound. However, the study found that PCBs bind poorly to the variant AHRs, which apparently blunts the chemicals’ effects.

Tomcod from cleaner waters occasionally carried mutant AHR2, suggesting that these variants existed in minor proportions prior to PCB pollution, says Dr. Wirgin. After the chemical was released, tomcod carrying the mutation had an advantage over others in the population because PCBs otherwise lead to lethal heart defects in young fish. The study’s findings suggest that this advantage drove genetic changes in these fish over some fifty years. “We think of evolution as something that happens over thousands of generations,” says Dr. Wirgin. “But here it happened remarkably quickly.”

The study co-authors are: Nirmal K. Roy and Matthew Loftus, the NYU School of Medicine; R. Christopher Chambers, the NOAA Fisheries Service, Highland, New Jersey; and Diana G. Franks and Mark E. Hahn, Woods Hole Oceanographic Institution.

About NYU School of Medicine:
NYU School of Medicine is one of the nation’s preeminent academic institutions dedicated to achieving world class medical educational excellence. For 170 years, NYU School of Medicine has trained thousands of physicians and scientists who have helped to shape the course of medical history and enrich the lives of countless people. An integral part of NYU Langone Medical Center, the School of Medicine at its core is committed to improving the human condition through medical education, scientific research and direct patient care. The School also maintains academic affiliations with area hospitals, including Bellevue Hospital, one of the nation’s finest municipal hospitals where its students, residents and faculty provide the clinical and emergency care to New York City’s diverse population, which enhances the scope and quality of their medical education and training. Additional information about the NYU School of Medicine is available at http://school.med.nyu.edu/.

Lorinda Klein | Newswise Science News
Further information:
http://www.nyumc.org

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>