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Objective: The Molecular Genetics of Schizophrenia (MGS2) project recruited an adult control sample of non-Hispanic European-ancestry (N=3,364) and African American (N=1,301) subjects. Method: Subjects gave consent to deposit phenotypic data and blood samples into a repository for general research use, with full anonymization of the sample. The authors compared the control sample with population census data for demographic data and with previous population surveys for anthropometrics and prevalences of psychiatric disorders as estimated by an Internet-administered questionnaire. Results: The full MGS2 control sample includes 4,665 subjects (European-ancestry: N=3,364; African American: N=1,301), of whom 3,626 were included in the MGS2 genome-wide association study (GWAS). The sample is generally demographically representative of the U.S. population, except for being older and more female, educated, and affluent, although all strata are represented. Self-reported ancestry was consistent with genotypic and census data. Lifetime prevalences for depressive, anxiety, and substance use diagnoses were higher than in previous population-based surveys, probably due to use of an abbreviated self-report instrument. However, patterns such as sex ratios, comorbidity, and demographic associations were consistent with previous reports. DNA quality for the Internet collected/evaluated control sample was comparable to that of the face-to-face case sample. Conclusions: The Internet-based methods facilitated the rapid collection of large and anonymized non-Hispanic European-ancestry and African American control samples that have been validated as being generally representative for many aspects of demography, ancestry, and morbidity. Utilization of clinical screening data shared with the scientific community may permit investigators to select appropriate controls for some studies.

Objective: The authors carried out a genetic association study of 14 schizophrenia candidate genes (RGS4, DISC1, DTNBP1, STX7, TAAR6, PPP3CC, NRG1, DRD2, HTR2A, DAOA, AKT1, CHRNA7, COMT, and ARVCF). This study tested the hypothesis of association of schizophrenia with common single nucleotide polymorphisms (SNPs) in these genes using the largest sample to date that has been collected with uniform clinical methods and the most comprehensive set of SNPs in each gene. Method: The sample included 1,870 cases (schizophrenia and schizoaffective disorder) and 2,002 screened comparison subjects (i.e. controls), all of European ancestry, with ancestral outliers excluded based on analysis of ancestry-informative markers. The authors genotyped 789 SNPs, including tags for most common SNPs in each gene, SNPs previously reported as associated, and SNPs located in functional domains of genes such as promoters, coding exons (including nonsynonymous SNPs), 3' untranslated regions, and conserved noncoding sequences. After extensive data cleaning, 648 SNPs were analyzed for association of single SNPs and of haplotypes. Results: Neither experiment-wide nor gene-wide statistical significance was observed in the primary single-SNP analyses or in secondary analyses of haplotypes or of imputed genotypes for additional common HapMap SNPs. Results in SNPs previously reported as associated with schizophrenia were consistent with chance expectation, and four functional polymorphisms in COMT, DRD2, and HTR2A did not produce nominally significant evidence to support previous evidence for association. Conclusions: It is unlikely that common SNPs in these genes account for a substantial proportion of the genetic risk for schizophrenia, although small effects cannot be ruled out.

Background: Cognitive deficits consistently have been reported in schizophrenia patients and in patients with schizotypal personality disorder. For this study, the authors wanted to identify which of the domains of cognitive impairment represent 'core' deficits of schizophrenia, comparing subjects with schizotypal personality disorder to two comparison groups: healthy volunteers and patients with personality disorders unrelated to schizophrenia. Method: Three groups completed a neuropsychological battery: patients with DSM-III-R schizotypal personality disorder (N=82); patients with DSM-III-R personality disorders unrelated to schizophrenia (i.e., a personality disorder other than schizotypal, schizoid, or paranoid [N= 44]); and healthy volunteers (N=63). The battery included the California Verbal Learning Test, Trailmaking Test parts A and B, the Dot test of working memory, the Stroop Color and Word Test, the Paced Auditory Serial Addition Test, the WMS visual reproduction test, and the WAIS-R vocabulary and block design. Results: Normative standards for performance that controlled for age, gender, and education were created from the scores of the healthy volunteers. Overall, schizotypal personality disorder patients performed significantly worse than the healthy volunteers and those with personality disorders unrelated to schizophrenia. Specifically, patients with schizotypal personality disorder demonstrated impaired performance on the Paced Auditory Serial Addition Test, WMS visual reproduction test, Dot test, and California Verbal Learning Test. In addition, in a regression analysis, performance on the Paced Auditory Serial Addition Test demonstrated the largest effect size. Indeed, it accounted for unique variance above and beyond all other cognitive measures, since controlling for Paced Auditory Serial Addition Test performance abolished group differences across all other measures. Conclusions: Patients with schizotypal personality disorder demonstrated moderate cognitive impairment compared with healthy volunteers (significant for seven out of 11 measures). These differences reached statistical significance for tasks of working memory, episodic memory, and delayed recall. Working memory performance accounted for the group differences. This study supports the view that working memory represents a core deficit of schizophrenia spectrum disorders.

Objective: Autism/autistic disorder (MIM number 209850) is a complex, largely genetic psychiatric disorder. The authors recently mapped a susceptibility locus for autism to chromosome region 2q24-q33 (MIM number 606053). In the present study, genes across the 2q24-q33 interval were analyzed to identify an autism susceptibility gene in this region. Method: Mutation screening of positional candidate genes was performed in two stages. The first stage involved identifying, in unrelated subjects showing linkage to 2q24-q33, genetic variants in exons and flanking sequence within candidate genes and comparing the frequency of the variants between autistic and unrelated nonautistic subjects. Two single nucleotide polymorphisms (SNPs) that showed evidence for divergent distribution between autistic and nonautistic subjects were identified, both within SLC25A12, a gene encoding the mitochondrial aspartate/glutamate carrier (AGC1). In the second stage, the two SNPs in SLC25A12 were further genotyped in 411 autistic families, and linkage and association tests were carried out in the 197 informative families. Results: Linkage and association were observed between autistic disorder and the two SNPs, rs2056202 and rs2292813, found in SLC25A12. Using either a single affected subject per family or all affected subjects, evidence for excess transmission was found by the Transmission Disequilibrium Test for rs2056202, rs2292813, and a two-locus G*G haplotype. Similar results were observed using TRANSMIT for the analyses. Evidence for linkage was supported by linkage analysis with the two SNPs, with a maximal multipoint nonparametric linkage score of 1.57 and a maximal multipoint heterogeneity lod score of 2.11. Genotype relative risk could be estimated to be between 2.4 and 4.8 for persons homozygous at these loci. Conclusions: A strong association of autism with SNPs within the SLC25A12 gene was demonstrated. Further studies are needed to confirm this association and to decipher any potential etiological role of AGC1 in autism.

Objective: The authors examined the relationship of borderline personality disorder to posttraumatic stress disorder (PTSD) with respect to the role of trauma and its timing. Method: The Trauma History Questionnaire and the PTSD module of the Structured Clinical Interview for DSM-III-R were administered to 180 male and female outpatients with a diagnosis of one or more DSM-III-R personality disorders. Path analysis was used to evaluate the relationship between borderline personality disorder and PTSD. Results: High rates of early and lifetime trauma were found for the subject group as a whole. Compared to subjects without borderline personality disorder, subjects with borderline personality disorder had significantly higher rates of childhood/adolescent physical abuse (52.8% versus 34.3%) and were twice as likely to develop PTSD. In the path analysis of the relationship between borderline personality disorder and PTSD, none of the different types of paths (direct path, indirect paths through adulthood traumas, paths sharing the antecedent of childhood abuse) was significant. The associations with both trauma and PTSD were not unique to borderline personality disorder; paranoid personality disorder subjects had an even higher rate of comorbid PTSD than subjects without paranoid personality disorder, as well as elevated rates of physical abuse and assault in childhood/adolescence and adulthood. Conclusions: The associations of personality disorder with early trauma and PTSD were evident, but modest, in borderline personality disorder and were not unique to this type of personality disorder. The results do not appear substantial or distinct enough to support singling out borderline personality disorder from the other personality disorders as a trauma-spectrum disorder or variant of PTSD.

Objective: Attentional deficits have been identified as an abnormality that individuals with schizotypal personality disorder share with schizophrenia patients. The purpose of this study was to examine automatic sensorimotor gating and controlled attentional modulation of the startle eye blink response in unmedicated subjects with schizotypal personality disorder. Method: Eighteen unmedicated patients with schizotypal personality disorder and 16 healthy individuals were assessed in an acoustic attention-to-prepulse paradigm. The participants performed a selective attention task involving the presentation of attended, ignored, and novel tones that served as prepulse tones. Acoustic startle probes were presented at short and long lead intervals after the onset of tones and occasionally during the intertone interval. Results: The comparison subjects showed greater prepulse inhibition and prepulse facilitation during the attended than the ignored prepulses, demonstrating early and later attentional modulation of startle eye blink response. In contrast, the subjects with schizotypal personality disorder failed to show this pattern. Conclusions: Subjects with schizotypal personality disorder have deficits in controlled attentional processing, as indexed by modification of the startle eye blink response, that are similar to those observed in patients with schizophrenia.

Objective: This study sought to understand affective instability among patients with borderline personality disorder by examining the degree of instability in six affective domains. The authors also examined the subjective intensity with which moods are experienced and the association between instability and intensity of affect. Method: In a group of 152 patients with personality disorders, subjective affective intensity and six dimensions of affective instability were measured. The mean scores for lability and intensity for each affective domain for patients with borderline personality disorder were compared with those of patients with other personality disorders through analyses that controlled for other axis I affective disorders, age, and sex. Results: Greater lability in terms of anger and anxiety and oscillation between depression and anxiety, but not in terms of oscillation between depression and elation, was associated with borderline personality disorder. Contrary to expectation, the experience of an increase in subjective affective intensity was not more prominent in patients with borderline personality disorder than in those with other personality disorders. Conclusions: By applying a finer-grained perspective on affective instability than those of previous personality disorder studies, this study points to patterns of affective experience characteristic of patients with borderline personality disorder.

Objective: The goal of this study was to identify chromosomal regions likely to contain schizophrenia susceptibility genes. Method: A genomewide map of 310 microsatellite DNA markers with average spacing of 11 centimorgans was genotyped in 269 individuals - 126 of them with schizophrenia-related psychoses - from 43 pedigrees. Nonparametric linkage analysis was used to assess the pattern of allele sharing at each marker locus relative to the presence of disease. Results: Nonparametric linkage scores did not reach a genomewide level of statistical significance for any marker. There were five chromosomal regions in which empirically derived p values reached nominal levels of significance at eight marker locations. There were p values less than 0.01 at chromosomes 2q (with the peak value in this region at D2S410) and 10q (D10S1239), and there were p values less than 0.05 at chromosomes 4q (D4S2623), 9q (D9S257), and 11q (D11S2002). Conclusions.' The results do not support the hypothesis that a single gene causes a large increase in the risk of schizophrenia. The sample (like most others being studied for psychiatric disorders) has limited power to detect genes of small effect or those that are determinants of risk in a small proportion of families. All of the most positive results could be due to chance, or some could reflect weak linkage (genes of small effect). Multicenter studies may be useful in the effort to identify chromosomal regions most likely to contain schizophrenia susceptibility genes.

Objective: The possible heterogeneity of the schizophrenia-related personality disorder traits associated with DSM-III criteria for schizotypal personality disorder was investigated using the family history method. A familial relationship to schizophrenia was hypothesized for schizophrenia-related personality disorder traits without coexisting affective personality disorder traits, pure schizophrenia-related personality disorder traits. Alternatively, a familial relationship with borderline personality disorder was hypothesized for schizophrenia-related personality disorder traits with comorbid affective personality disorder traits. Method: Criteria for schizophrenia-related and affective personality disorder traits were used to assess the 588 nonpsychotic first-degree relatives of 55 chronic schizophrenic probands and 67 probands with personality disorders. The probands with one or more DSM-III personality disorders were categorized as having schizotypal personality disorder without borderline personality disorder (pure schizotypal personality disorder), borderline personality disorder without schizotypal personality disorder (pure borderline personality disorder), both disorders, or neither. Results: The morbid risk of all cases of schizophrenia-related personality disorder traits was higher in relatives of probands with schizophrenia and pure schizotypal personality disorder than in relatives of probands with neither schizotypal nor borderline personality disorder; however, it differed only slightly from that observed in the relatives of probands with both schizotypal and borderline personality disorders and pure borderline personality disorder. In contrast, the risk of pure schizophrenia-related personality disorder traits was higher in relatives of probands with schizophrenia and pure schizotypal personality disorder, while the risk of coexisting schizophrenia-related and affective personality disorder traits was lower in both of these groups than among the relatives of probands with both schizotypal and borderline personality disorders and pure borderline personality disorder. Conclusions: These results offer preliminary indications that schizotypal personality disorder features present without comorbid affective personality disorder traits may more specifically characterize the personality characteristics familially related to schizophrenia. Furthermore, they indicate that schizotypal personality disorder features as currently defined are found in relatives of patients other than those with schizophrenia or schizotypal personality disorder.

Some researchers have hypothesized that borderline personality disorder, marked by affective instability and impulsivity, is linked to a familial history of affective disorder (mood disorder, such as depression or bipolar disorder). However, more recent research suggests that this is only true if the patient with borderline personality disorder also suffers from an affective disorder. Borderline personality disorder and related traits seem to aggregate within families. In the present study, family interviews were used to obtain family history information for 64 patients with personality disorders. Patients completed several scales for personality assessment and data were compared with data from 43 schizophrenics and their families. Of the 64 patients with personality disorders, 29 were diagnosed with borderline personality disorder and 22 had other personality disorders, but possessed three or fewer traits of borderline personality disorder. In all, 129 relatives of borderline personality disorder patients were interviewed, along with 105 relatives of those with other personality disorders and 218 relatives of schizophrenics. Statistical analysis showed that the risks for affective and impulsive personality traits were greatest for family members of those with borderline personality disorder. This suggests that there may be familial transmission of borderline personality disorder characteristics. (Consumer Summary produced by Reliance Medical Information, Inc.)

Objective: This study attempted to examine the relationship between month and season of birth and risk for autism spectrum disorders. Method: The cohort included all Jewish individuals born in Israel over 5 consecutive years (N=311,169) and assessed by the Israeli Draft Board as part of the mandatory assessment of eligibility for military service conducted at age 17. The outcome of autism spectrum disorders was ascertained from the Draft Board Medical Registry, which contains information about medical and psychiatric disorders for this population of adolescents. Results: There was no association between month or season of birth and the prevalence of autistic spectrum disorders. Conclusions: The findings from this historical, populationbased cohort study do not support an association between season of birth and autistic spectrum disorders.