Background
Schizophrenia is a chronic mental disorder with different symptoms. The environmental and genetic factors are suggested to be the etiology of schizophrenia. However, the exact cause and pathogenesis of schizophrenia are still unclear. Different studies suggested that the immune system may have a role in schizophrenia. A genetic study found a relation between the disease and the HLA region on the sixth chromosome. Regulatory T cells (Treg) have a role in the regulation of immune response, especially the balance between TH1 and TH2 cells. The FOXP3 protein is a key regulator for Treg cell's functions. FOXP3 is a transcriptional factor, and its gene is present on the short arm of the X chromosome. The selected SNPs present in the promoter region which act as binding sites for transcriptional factors. This study investigated FOXP3 gene polymorphisms (rs3761548, rs3761549, and rs2232365) in Egyptian patients with schizophrenia. There are no previous studies about the association of FOXP3 gene polymorphisms with schizophrenia. The three selected single-nucleotide polymorphisms (SNPs) were investigated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for 125 schizophrenia patients and 160 healthy controls. The Positive and Negative Syndrome Scale (PANSS) was used to evaluate patients with schizophrenia.
Conclusion
The ATC haplotype of rs2232365, rs3761549, and rs3761548 could be considered a risk factor for schizophrenia in Egyptian patients.
Results
No significant associations were found between schizophrenia patients and healthy controls for the alleles and genotypes of the selected SNPs (P-value > 0.05). However, a significant association with ACC and ATC haplotypes was detected (P-value 0.001). No significant association was detected between the PANSS score and any of the studied SNPs.