BackgroundAutism spectrum disorder (ASD) is a pediatric heterogeneous psychiatric and neurodevelopmental disorder with social and communication deficits, language impairment and ritualistic or repetitive behaviors. ASD has significant genetic bases but candidate genes and molecular mechanisms of disorder are not clarified. Neuregulin1 (NRG1) gene, located in 8p12 is involved in development of central nervous system and was indicated as candidate gene in schizophrenia.MethodsmRNA level of types I, II and III of NRG1 gene were studied in peripheral blood of 1540 ASD patients (IQ > 70) and 1490 control children by quantitative Real Time PCR. Also three domains of executive functions (working memory, response inhibition and vigilance) were examined in all subjects.FindingsAll three types were significantly down regulated in ASD patients. Significant deficiencies in executive functions (EF) were found in ASD patients. EF deficiencies mostly were associated with down expression of mRNA level of types I and III. Also correlations were found between NRG1 expression with gender and severity of ASD symptoms.InterpretationsFindings primarily have been suggested involvement of NRG1 in etiology of ASD. Also correlation of NRG1 mRNA level with EF deficiencies could shed lights on EF mechanisms and may suggest targeted treatments to improve particular executive functions.FundYoung researchers and elites club funded the project due to the annual grant of special talents of Club that gave to Arvin Haghighatfard.

No abstract

No abstract

Introduction: Schizophrenia (SCZ) is a major psychiatric disorder with unclear etiology or biological diagnosis. Paranoid Personality Disorder (PPD) is a type A personality disorder characterized by paranoia and generalized mistrust. Disrupted in schizophrenia 1 (DISC1) is a gene located on human chromosome 1 that is involved in neurodevelopment of brain. Variations and translocations in this gene were found associated with schizophrenia and other psychiatric disorders. Present study aimed to evaluate the expression alteration of DISC1 gene in peripheral blood of SCZ and PPD patients and its correlation with clinical features. Material and methods:Study was included 300 SCZ, 300 PPD and 300 non-psychiatric individuals. Total blood was collected and expression level of DISC1 evaluated by using quantitative Real time PCR SYBR green. Lymphocyte DISC1 protein levels in all subjects were examined. Also, to assess psychiatric symptoms severity, Positive and Negative Syndrome Scale (PANSS) was obtained from SCZ and PPD patients. For analysis of executive functions abilities, Wisconsin Card Sorting Test (WCST) had been conducted from all subjects.Results: Findings showed significant DISC1 gene down expression in SCZ and PPD patients vs. non-psychiatrics. DISC1 protein levels were significantly decreased in SCZ and PPD vs. non-psychiatrics. Also in SCZ patients, general and negative symptoms score were associated with down regulation of DISC1 mRNA level. Executive functions deficiency had detected in SCZ and PPD and correlations were found between decrease in WSCT correct response and down expression of DISC1 in SCZ and PPD patients. Discussion and conclusion:Results presented DISC1 as potential peripheral marker for schizophrenia as well as paranoid personality disorder. Correlation between DISC1 mRNA level reduction and severity of general and negative symptoms in one side and executive functions abnormalities in the other side may support the neurodevelopment hypothesis about pathophysiology of schizophrenia and related personality disorder especially paranoid personality disorder.

No abstract