Participants were recruited from urban, suburban, and rural populations across the United States and in selected sites abroad. Individuals suffering from schizophrenia or bipolar disorder are ascertained as in-patients in acute care or chronic care settings, out-patients, or community dwelling. All subjects will be 18 or older. Both males and females will be actively recruited, including pregnant females and hospitalized patients. All cases meet lifetime diagnostic criteria for schizophrenia (any subtype) in accordance with the OPCRIT algorithms for DSM-IV and/or ICD-10 criteria. Control participants were drawn from the same geographic area as case participants, either within health care facilities or as community volunteers. Both potential cases (patients suffering with schizophrenia and bipolar disorder) and controls (unaffected participants) were asked to complete a questionnaire (Screening Questionnaire) to assess their psychiatric history.