The identification of autism susceptibility genes has moved a step closer over the last four years with the completion of eight whole genome screens for linkage. Several overlapping areas of linkage have been reported, most notably on chromosomes 7q22-31 and 2q32. These regions of replicated linkage provide a focus to search for candidate genes whose normal functions in neurodevelopment are altered to increase the risk for autism. Strategies that aim to narrow further the rather broad size of...