Jason is a gastroenterologist and researcher with an interest in coeliac disease. He heads the Coeliac Research Lab at the Walter and Eliza Hall Institute where his research aims to understand the immune and genetic basis for why gluten is harmful for people with coeliac disease. He is involved in the care of patients with gluten-related issues at The Royal Melbourne Hospital and in private practice. He participates in university, hospital and community-based education of physicians, GPs, dietitians and students. He is an inventor on patents pertaining to the use of gluten peptides in coeliac disease diagnosis and treatment. Jason chairs the Medical Advisory Committee of Coeliac Australia.