Malic enzyme 2 and susceptibility to psychosis and mania.

Previous studies have identified a putative gene locus for both schizophrenia and bipolar disorder in the chromosome 18q21 region. To identify candidate genes associated with these disorders we completed fine mapping analyses (using microsatellite markers) in 152 families from the Central Valley of Costa Rica (CVCR) (376 total subjects, 151 with a history of psychosis, 97 with a history of mania). Microsatellite analyses showed evidence of association at two contiguous markers, both located at the same genetic distance and spanning approximately 11 known genes.