Genes give clues to cheetah's spots

The gene that helps give tigers their stripes has been identified by researchers with ties to Stanford and Alabama's HudsonAlpha Institute for Biotechnology. The researchers say new genetic findings help explain why cheetahs have spots and tabby cats have stripes. "Until now, there's been no obvious biological explanation for cheetah spots or the stripes on tigers, zebras or even the ordinary house cat," Dr. Gregory Barsh, faculty investigator at HudsonAlpha and emeritus professor of genetics at Stanford University, said in a statement Friday. Sequence differences between striped and blotched domestic cats pointed to a gene researchers named Taqpep. Researchers said their examination of genes expressed in dark versus light hair cells revealed patterned markings are due to variations in another gene, Edn3, being expressed at high levels in the darkly colored hair cells. "The researchers thus suggest that the Taqpep gene helps to establish either a periodic pattern for stripes or a spotted or blotched pattern, by determining the level of Edn3 expressed in each skin area at an early stage of the cat's development," HudsonAlpha's release said. Barsh said discovery of new genetic pathways and mechanisms is the foundation for understanding the blueprint encoded in any genome, including humans. "Uncovering new biologic principles in animals that are more closely related to humans, like cats, dogs and laboratory mice, may reveal unexpected insights with far-reaching implications for human biology and disease," he said. The findings are published in the Sept. 21 issue of Science.