Correlation of rs35753505 polymorphism in Neuregulin 1 gene with psychopathology and intelligence of people with schizophrenia

•In this study, correlations between rs35753505 SNP of NRG1 gene with schizophrenia, psychopathology and verbal intelligence were analyzed.•Our results show that rs35753505 polymorphism of NRG1 is associated with schizophrenia.•Our results recommend that the correlation between two variables, the rs35753505 polymorphism significantly increases the PANSS test results.•Investigating the coexistence of alleles and genotypic correlation of Neuregulin 1 (NRG1) mononucleotide polymorphism rs35753505, with psychopathology and intelligence in different ethnicities with more population is encouraged. Schizophrenia is one of the most severe psychiatric disorders. About 0.5 to 1% of the world's population suffers from this non-Mendelian disorder. Environmental and genetic factors seem to be involved in this disorder. In this article, we investigate the alleles and genotypic correlation of mononucleotide rs35753505 polymorphism of Neuregulin 1 (NRG1), one of the selected genes of schizophrenia, with psychopathology and intelligence. 102 independent and 98 healthy patients participated in this study. DNA was extracted by the salting out method and the polymorphism (rs35753505) were amplified by polymerase chain reaction (PCR). Sanger sequencing was performed on PCR products. Allele frequency analysis was performed using COCAPHASE software, and genotype analysis was performed using Clump22 software. According to our study's statistical findings, all case samples from the three categories of men, women, and overall participants significantly differed from the control group in terms of the prevalence of allele C and the CC risk genotype. The rs35753505 polymorphism significantly raised Positive and Negative Syndrome Scale (PANSS) test results, according to a correlation analysis between the two variables. However, this polymorphism led to a significant decrease in overall intelligence in case samples compared to control samples. In this study, it seems that the rs35753505 polymorphism of NRG1 gene has a significant role in the sample of patients with schizophrenia in Iran and also in psychopathology and intelligence disorders.