Stem Cell Research on Subjects at Genetic High Risk for Schizophrenia

Inclusion Criteria: \[Subjects at genetic high risk for schizophrenia\] * Healthy without any Axis I mental disorder * Is a monozygotic twin of a patient with schizophrenia OR Has at least two family members of schizophrenia in the pedigree, including at least one 1st-degree family member \[Healthy Control\] * Healthy without any Axis I mental disorder * No family members of schizophrenia in the pedigree to the 3rd degree Exclusion Criteria: * Significant neurological or medical illness * Psychotic symptoms * Substance abuse * Suicidal risk * Blindness or hearing loss * Taking aspirin, warfarin or hormonal agents * Pregnancy or lactation * Susceptibility for keloid formation * Allergy to lidocaine * History of significant head trauma or loss of consciousness * Mental retardation