Gene mutations cause not only well-recognized rare diseases such as muscular dystrophy and cystic fibrosis, but also thousands of other rare disorders. While individually rare, these disorders are collectively common, affecting one to three percent of the population. It is estimated that as many as half of Canadians with rare disorders are undiagnosed. Drs. Kym Boycott, Alex MacKenzie and team will use powerful new gene sequencing technologies to identify the genes implicated in many of these rare diseases. Besides providing important new understanding into human disease, this project will yield other benefits, including: avoiding invasive procedures, stopping ineffective treatments, developing earlier and better diagnoses, devising more appropriate treatment, and predicting the chances that one of these rare diseases could be passed on to offspring. Once the disease-causing genes have been identified, researchers will test drugs that are currently on the market to identify those that might be effective against these rare diseases.