ObjectivesNeuregulin 1 (NRG1) is a risk gene for schizophrenia and involved in neurodevelopment and synaptic plasticity. Polymorphisms in NRG1 may affect psychotic symptoms in schizophrenia. This study investigated the effects of the single nucleotide polymorphism (SNP) rs6982890 on peripheral plasma NRG1 immunoreactivity, clinical symptoms and cognitive functions in schizophrenia patients. Material and methodsWe recruited subjects from the Han population of northern China from 2010 to 2022. We first genotyped and analyzed 6 NRG1 SNPS in 1304 patients with schizophrenia and 871 healthy controls. Then, 91 patients with schizophrenia and 40 healthy controls were selected to detect the peripheral plasma NRG1 immunoreactivity by ELISA. Among them, 84 patients were divided into rs6982890 genotypes to analyze the correlation between NRG1 immunoreactivity and clinical symptoms. ResultsRs6982890 allelic frequencies were statistically significant between patients and controls. Baseline peripheral plasma NRG1 immunoreactivity in patients were significantly lower than controls. NRG1 immunoreactivity in patients were significantly increased after 8 weeks of antipsychotic treatment and significantly correlated with clinical symptoms and cognitive function. Genotyping of patients with SNP rs6982890 indicated NRG1 immunoreactivity in CC genotype increased significantly after treatment, while CT genotype had no significant change. Baseline NRG1 immunoreactivity with the CT genotype were significantly higher than CC genotype. ConclusionsNRG1 SNP rs6982890 is significantly associated with schizophrenia in the Han population of northern China, and it may affect the effect of antipsychotic drug treatment by regulating the peripheral plasma NRG1 immunoreactivity.