U.S. government scientists have demonstrated that a miniature positron emission tomography (PET) scanner, known as microPET, and the chemical markers used in traditional PET scanning are sensitive enough to pick up subtle differences in neurochemistry between known genetic variants of mice. This “proof-of-principle” experiment “opens up a whole new, non-invasive way to study and follow transgenic or genetically engineered strains of mice that serve as animal models for human neurological diseases, such as Parkinson’s and Alzheimer’s disease or psychiatric diseases such as substance abuse, depression, and anxiety disorders,” said Panayotis (Peter) Thanos, lead author of the study.