Type-1 diabetes is a life-long disorder that often occurs in children or young adults. Susceptibility to type-1 diabetes is believed to be dependent on both genetic and environmental causes. Genetic screening is becoming a common tool for evaluating risk, potentially before the onset of the disease. However, interpreting the results of genetic tests involves many rules taken from the literature on the correlation between risk and genetic markers. We introduce an expert system based approach in which the evaluation of risk for type-1 diabetes can be automated. This method can act as a tool for medical professionals and provides the crucial explanatory component, including citations to the relevant literature. The expert system was developed in conjunction with geneticists. As part of the corresponding clinical trial, the expert system correctly identified the at-risk genetic profiles in a set of 253 subjects evaluated by human experts.