The genome of the platy (Xiphophorus maculatus), that endearing little freshwater fish that produces prodigious amounts of live young in the aquarium, has been decoded by scientists with the Washington University School of Medicine in St. Louis, the University of Würzburg in Germany and Texas State University. The platy is unique in the fish world for its tendencies to develop melanomas, which makes them an ideal subject for exploring cancers.
“In platyfish, melanomas typically develop as black splotches along the tail and fins,” senior author Wesley Warren, Ph.D, a geneticist at Washington University’s Genome Institute said in a news release detailing the research put out by Washington University. “These fish are an ideal model for exploring the many unknowns of cancer, including how, when and where it develops in the body as well as its severity.”
With the genome decoded, the scientists will now determine how the genes interact together to cause melanomas, what genes play a role in the pigment cells and how they influence the development of melanoma in the fish. The platy has close to 20,000 genes, around the same number found in the human genome, but apparently these genes have remained static for more than 200 million years of evolution, the report said. The scientists also found that the livebearing fish also retained yolk-related genes typically found in egg layers. The scientists also found gene copies that are linked to cognition in humans and other mammals that could be the reasons that platy fish have evolved complex behaviors such courting, schooling and predator avoidance, traits that exceed the capabilities of amphibians, reptiles, and other lower vertebrates, the report said.
The research was funded by the National Institutes of Health, National Center for Research Resources and the Office of Research Infrastructure Programs, and the paper, “The genome of the platyfish, Xiphophorus maculatus, provides insights into evolutionary adaption and several complex traits” appeared in the March 31, 2013 issue of Nature Genetics.
The platy is one of the most popular freshwater aquarium fish in the hobby. It comes in a variety of colors, is hardy, and is a prolific breeder. It is closely related to the swordtail and is a great fish for beginners.
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