Initial results from research designed to discover genetic markers that may predict individuals at risk for serious drug induced liver injury (DILI) have been released. Analysis of a subset of DNA patients has led to the discovery that HLA-B*5701 is a major determinant of liver injury induced by flucloxacillin. Flucloxacillin is an antibiotic widely used in Europe and Australia, mainly in the treatment of staphylococcal infections.