The ASD-like behaviours of Lrfn2 KO mice led us to conduct a pilot survey of mutations in human LRFN2. LRFN2 protein-coding exons and flanking introns were sequenced in DNA samples from 165 individuals with autism and 910 patients with schizophrenia and 1,060 mentally healthy controls. The gene discussed is LRFN2; the disease is autism.