Investigation of repeatability of presence and effect of the rs3918242 in patients with autism spectrum disorder

Autism spectrum disorder (ASD) is a clinically heterogeneous neurologic diseases collection characterized by deficits in social and communication. There are some essential genes including CNTNPA2 and MMP9. Matrix Metalloproteinase-9 (MMP9) is expressed by astrocytes, and microglia which play an important role in neuroinflammation. In this project, we aimed to analyze the association of MMP-9 (rs3918242) gene polymorphism and its serum levels with ASD. 170 patients with ASD and 125 controls subjects were enrolled in this study. Genomic DNA was extracted from peripheral blood samples using triton X100 solution kit and the MMP-9 nucleotide polymorphism were determined by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). The serum level of MMP-9 was measured by enzyme-linked immunosorbent assay (ELISA). The results showed that the frequencies of CC, CT and TT genotypes of MMP-9 were 67%, 31% and 2% in controls and 31%, 57% and 12% in ASD, respectively (P=0.0001). The frequencies of C and T allele in ASD patients were 59%, 41% and the controls was 83% and 17%, respectively (P=0.0001). Significant association was observed in genotypes and allele distributions of between two groups (P<0.05). We have also showed that there is a significant change in serum MMP-9 expression in ASD patients as compared to controls. It is concluded that there is a significant association between rs3918242 MMP9 gene polymorphism and serum levels of MMP-9 with autism in the studied population. It is also suggested that MMP-9 may play a role in pathophysiology of ASD.

Keywords:

ASD , Polymorphism , MMP9 , rs3918242