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Objective: The Consortium on the Genetics of Schizophrenia has undertaken a large multisite study to characterize 12 neurophysiological and neurocognitive endophenotypic measures as a step toward understanding the complex genetic basis of schizophrenia. The authors previously demonstrated the heritability of these endophenotypes; in the present study, genetic linkage was evaluated., Method: Each family consisted of a proband with schizophrenia, at least one unaffected sibling, and both parents. A total of 1,286 participants from 296 families were genotyped in two phases, and 1,004 individuals were also assessed for the endophenotypes. Linkage analyses of the 6,055 single-nucleotide polymorphisms that were successfully assayed, 5,760 of which were common to both phases, were conducted using both variance components and pedigree-wide regression methods., Results: Linkage analyses of the 12 endophenotypes collectively identified one region meeting genome-wide significance criteria, with a LOD (log of odds) score of 4.0 on chromosome 3p14 for the antisaccade task, and another region on 1p36 nearly meeting genome-wide significance, with a LOD score of 3.5 for emotion recognition. Chromosomal regions meeting genome-wide suggestive criteria with LOD scores >2.2 were identified for spatial processing (2p25 and 16q23), sensorimotor dexterity (2q24 and 2q32), prepulse inhibition (5p15), the California Verbal Learning Test (8q24), the degraded-stimulus Continuous Performance Test (10q26), face memory (10q26 and 12p12), and the Letter-Number Span (14q23)., Conclusions: Twelve regions meeting genome-wide significant and suggestive criteria for previously identified heritable, schizophrenia-related endophenotypes were observed, and several genes of potential neurobiological interest were identified. Replication and further genomic studies are needed to assess the biological significance of these results.

Objective: The authors used a custom array of 1,536 single-nucleotide polymorphisms (SNPs) to interrogate 94 functionally relevant candidate genes for schizophrenia and identify associations with 12 heritable neurophysiological and neurocognitive endophenotypes in data collected by the Consortium on the Genetics of Schizophrenia., Method: Variance-component association analyses of 534 genotyped subjects from 130 families were conducted by using Merlin software. A novel bootstrap total significance test was also developed to overcome the limitations of existing genomic multiple testing methods and robustly demonstrate significant associations in the context of complex family data and possible population stratification effects., Results: Associations with endophenotypes were observed for 46 genes of potential functional significance, with three SNPs at p<10(-4), 27 SNPs at p<10(-3), and 147 SNPs at p<0.01. The bootstrap analyses confirmed that the 47 SNP-endophenotype combinations with the strongest evidence of association significantly exceeded that expected by chance alone, with 93% of these findings expected to be true. Many of the genes interact on a molecular level, and eight genes (e.g., NRG1 and ERBB4) displayed evidence for pleiotropy, revealing associations with four or more endophenotypes. The results collectively support a strong role for genes related to glutamate signaling in mediating schizophrenia susceptibility., Conclusions: This study supports use of relevant endophenotypes and the bootstrap total significance test for identifying genetic variation underlying the etiology of schizophrenia. In addition, the observation of extensive pleiotropy for some genes and singular associations for others suggests alternative, independent pathways mediating pathogenesis in the "group of schizophrenias."

Objective: This study of women Veterans Affairs (VA) health care patients screened for the prevalence of past-year smoking, hazardous and problem drinking, other drug abuse, and psychiatric disorders., Methods: A survey was mailed to women veterans who had received care from VA Puget Sound Health Care System between October 1, 1996, and January 1, 1998. Screening measures included questions about cigarettes; questions from the Alcohol Use Disorders Identification Test about consumption (hazardous drinking); the TWEAK test (problem drinking); a drug abuse screen; the Patient Health Questionnaire (psychiatric conditions); and the PTSD (posttraumatic stress disorder) Checklist., Results: Of eligible patients, 1,257 (65 percent) returned surveys with complete substance use data. Patients reported a relatively high rate of past-year smoking (29.1 percent) and hazardous drinking, problem drinking, or both (31.1 percent). The rate of past-year drug use was much lower (4.9 percent). Younger age was strongly associated with greater substance abuse: 59 percent of women under age 35 screened positive for smoking, hazardous or problem drinking, or drug abuse. Screening positive for a psychiatric condition (N=504) was also associated with substance abuse: The rate of past-year drug abuse among women screening positive for a psychiatric condition (9.7 percent) was double the rate for the entire sample. Of the women who screened positive for depression, PTSD, eating disorders, or panic disorders, 57 percent screened positive for substance abuse (including smoking)., Conclusions: Substance abuse is common among women VA patients and is associated with younger age and with screening positive for other psychiatric conditions. Providers are expected to follow up on positive screening tests, and these data indicate substantial provider burden.