Serotonin receptor gene allele polymorphism (5HTR2A) and clinical pathogenetic characteristics in patients with schizophrenia and schizophrenia spectrum disorders

: Serotonin receptor 5HTR2A gene polymorphism was reported to be associated with psychiatric disorders, in particular schizophrenia, in numerous studies. This study aimed to analyze a possible association between 5HTR2A gene polymorphism and clinical and pathogenetic characteristics in schizophrenia and schizophrenia spectrum disorders. We studied 209 individuals with schizophrenia and related disorders (107 male and 102 female, mean age 34.7 +/- 17.2 years) and 116 healthy controls (44 males, 72 females, mean age = 33.6 +/- 14.4 years). Diagnoses were made according diagnostic criteria of ICD-10. Positive and Negative Symptoms Scale (PANSS) assessed clinical symptoms. Significant difference (p < 0.01) was found for 5HTR2A genotype distribution between affected and control groups. The frequencies of genotypes A1A1, A1A2 and A2A2 for schizophrenia were 13.3%, 44.0% and 42.7%, respectively, versus 33%, 47% and 27% in controls. These results support the evidence for association between 5HTR2A A2A2 genotype and schizophrenia. Schizophrenics with A2A2 genotype were characterized by significantly higher mean values of the PANSS negative symptoms subscale than those with A1A1 genotype (22.6 vs 17.8; p < 0.05) and, consequently, by majority of deficit patients and patients with more severe forms of schizophrenia. Patients with A1A1 genotype were younger compare to those with A2A2 genotypes and had the least familial factors (35.7% vs 46.1%). In agreement with the results obtained in the study the 5HTR2A gene polymorphism appears to be considered as additional diagnostic or prognostic trait in the medical genetic studies of schizophrenia.