Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fish cancer gene linked to pigment pattern that attracts mates

20.08.2008
Swordtails can inherit melanoma that drives sexual selection

Though skin cancer is deadly to male fish, it also has one perk: The black melanoma splotches arise from attractive natural markings that lure female mates.

A new study published in the Proceedings of the National Academy of Sciences this week shows that the melanoma gene can be conserved in swordtail fish because of its beneficial role in sexual selection.

Ohio University scientists André Fernandez and Molly Morris studied three populations of female swordtails, tiny freshwater fish native to North and Central America, and found that two of them preferred males whose tails were painted to resemble the skin cancer spots. The researchers also examined specimens of swordtail fish with real melanomas, which confirmed that the cancer gene is switched on only in the tissue with the dark pigment. The study marks the first time scientists have found a cancer gene linked to a pigment pattern that functions to increase mating success in animals.

In the current study, the researchers placed a female swordtail in the middle of a tank with two partitions. They positioned a male with the faux pattern from which melanomas form on one side, and a male without the pattern on the other. After releasing the female from an opaque tube into the tank's center chamber, the scientists observed how much time she spent looking at each male during an eight-minute period. The project builds on previous studies in the Morris lab, which used the same tests to show that female swordtails are strongly attracted to males with dark vertical bars.

To avoid any bias the female might have for a particular side of the tank, Fernandez then switched the males. Two days later, he conducted the trials again, this time changing which male received the painted skin cancer spot. The female consistently chose the male with the dark pigmented marking in two of the three populations, he said.

But the research suggests that the swordtail fish population also keeps the prevalence of the cancer gene in check. A third population of females in the study rejected the males painted with the pattern that can form melanomas. The scientists suspect that's because the third group had a higher ratio of both males and females with the gene for skin cancer, which increases the likelihood of too many offspring inheriting the gene and dying off.

Swordtail fish usually live for 1.5 to 2 years in the wild and sexually mature at 4.5 months. The ones with the skin cancer gene can develop melanomas at about 7 months and die a few months later.

"Melanoma formation cuts the reproductive life cycle in half," Fernandez said. "It has a huge cost for males."

But during the few months when the male is sexually mature and healthy, he also can produce a lot of offspring, he noted.

The swordtail melanoma has been studied since the 1920s, and scientists previously believed that fish developed the cancer only in captivity. But in the recent study, 10 percent of the swordtails collected from the third population in Mexico also exhibited the disease, said Fernandez, who joins the University of Texas M.D. Anderson Cancer Center this fall as a postdoctoral fellow. He hopes to conduct further studies on the habitat, such as whether stronger exposure to the sun's UV rays might be driving more instances of skin cancer in the wild.

Andrea Gibson | EurekAlert!
Further information:
http://www.ohio.edu

More articles from Life Sciences:

nachricht New method to rapidly map the 'social networks' of proteins
27.06.2017 | Salk Institute

nachricht X-ray experiments reveal two different types of water
27.06.2017 | Deutsches Elektronen-Synchrotron DESY

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

Collapse of the European ice sheet caused chaos

27.06.2017 | Earth Sciences

NASA sees quick development of Hurricane Dora

27.06.2017 | Earth Sciences

New method to rapidly map the 'social networks' of proteins

27.06.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>