Affiliation: | aLaboratory of Tumor Biology, Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts, 02129;bDepartment of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030;cMRC Mammalian Genetics Unit, Harwell, Oxon, OX11 ORD, United Kingdom;dMolecular Neurogenetics Unit, Massachusetts General Hospital, Charlestown, Massachusetts, 02129 |