In Science this week, two international research teams publish genomic studies of ancient animals, uncovering new details about their evolution and domestication. In the first study, researchers use DNA from modern and ancient dogs to investigate domesticated dogs that lived in the Americas prior to the arrival of Europeans. They find that these animals are most closely related to a 9,000-year-old ancient breed of sled dogs from Eastern Siberia and that they were not domesticated in the Americas but rather introduced by Beringia settlers. In the second paper, investigators focus on the domestication of goats in the Fertile Crescent using genetic data from specimens from Paleolithic through Medieval periods throughout the Near East. They find evidence that multiple divergent ancient wild goat sources were domesticated in a dispersed process that resulted in genetically and geographically distinct Neolithic goat populations. They also detect early selection for pigmentation, stature, reproduction, milking, and response to dietary change as early as 8,000 years ago. GenomeWeb has more on these studies, here and here.
And in Science Translational Medicine, researchers from the US National Institutes of Health, Vertex Pharmaceuticals, and others report data showing how certain mutations drive rhabdomyosarcoma, a cancer of the muscle that primarily affects children, and how another cancer drug may be used to treat the condition. Using genome-wide approaches, the researchers show that mutated RAS proteins in rhabdomyosarcoma prevent muscle cell differentiation by inhibiting the expression of the protein MYOG. High-throughput drug screening revealed that MEK inhibitors can reverse MYOG inhibition and induce cancer cell differentiation. One MEK inhibitor in particular — the melanoma drug trametinib — was found to restore MYOG expression, slow tumor growth, and improve survival in RAS-mutated rhabdomyosarcoma mouse models when used in combination with an IGF1R inhibitor.