NIH selects 9 faculty members for grants to boost innovative research

Feral cats in northern california have enabled researchers to unlock the biological secret behind a rare, striped cheetah found only in subSaharan africa, according to researchers at the School of medicine, the national cancer institute and Hudsonalpha institute for Biotechnology in Huntsville, alabama. the study is the first to identify a molecular basis of coat patterning in mammals. the scientists found that the two felines share a biological mechanism responsible for both the elegant stripes on the tabby cat and the cheetah’s normally dappled coat. dramatic changes to the normal patterns occur when this pathway is disrupted: the resulting house cat has swirled patches of color rather than orderly stripes, and the normally spotted cheetah sports thick, dark lines down its back. “mutation of a single gene causes stripes to become blotches, and spots to become stripes,” said Greg Barsh, md, Phd, emeritus professor of genetics and of pediatrics at Stanford and an investigator at the Hudsonalpha institute. the differences are so pronounced that biologists at first thought that cheetahs with the mutated gene belonged to an entirely different species. the rare animals became known as “king cheetahs,” while affected tabby cats received the less-regal moniker of “blotched.” (the more familiar, striped cat is known as a mackerel tabby.) the study was published Sept. 21 in Science. christopher Kaelin, Phd, a senior scientist in the Barsh laboratory, is the co-first author; Xiao Xu, Phd, from the national cancer institute-frederick national Laboratory for cancer research and the Sichuan Key Laboratory of conservation Biology on endangered Wildlife in Sichuan, china, is the other co-first author. marilyn menotti-raymond, Phd, of nci-frederick is the senior author. Barsh and his lab members have spent decades investigating how traditional laboratory animals such as mice develop specific coat colors. His previous work identified a variety of biologically important pathways that control more than just hair or skin color, and have been linked to brain degeneration, anemia and bone marrow failure. But laboratory mice don’t display the pattern variation seen in many mammals. “We were motivated by a basic question,” said Barsh of the turn to the study of big (and little) cats. “How do periodic patterns like stripes and spots in mammals arise? What generates them? How are they maintained? What is their biological and evolutionary significance? it’s kind of surprising how little is known. Until now, there’s been no obvious biological explanation for cheetah spots or the stripes on tigers, zebras or even the ordinary house cat.” the research relied primarily on dna samples from feral cats in northern california captured for sterilization and release, on tissue samples provided by the city of Huntsville animal How the cheetah got stripes: A genetic tale