Evidence for two schizophrenia susceptibility genes on chromosome 22q13.

Objective: Previous linkage scans and meta-analyses for schizophrenia susceptibility loci failed to include the most distal portion of chromosome 22q. Accordingly, 27 families having individuals affected with schizophrenia and schizophrenia-spectrum disorders were analyzed using a set of highly informative markers covering all of chromosome 22q.

Methods: Microsatellite and single nucleotide polymorphism markers were evaluated by nonparametric linkage, parametric linkage, and transmission disequilibrium testing of 22q.