Tissue samples of arteriovenous malformations of the brain were obtained from 72 patients. The majority of the samples had an activating mutation in KRAS, a gene previously implicated in tumorigenesis. Video: Phenotype of Endothelial Cells after KRAS Activation. Full study: http://nej.md/2CzIBdQ | The New England Journal of Medicine

695K views · 20K reactions | Do You Know? Some cats are born with a genetic mutation called polydactylism, giving them extra toes—some have up to 28! While most people know cats purr when happy, few realize they also purr when scared or in pain as a self-healing mechanism. There’s also a breed called the Lykoi, known as the “werewolf cat” due to its unique, patchy coat and eerie look. | Paw Plaza | Facebook