Mahsa Delshadpour - MSc, Department of Biology, Faculty of Sciences, University of Guilan, Rasht, Iran
Farhad Mashayekhi - PhD, Department of Biology, Faculty of Sciences, University of Guilan, Rasht, Iran
Elham Bidabadi - Faculty of Medicine, Guilan University of Medical Sciences, Rasht, Iran
Shirin Shahangian - PhD, Department of Biology, Faculty of Sciences, University of Guilan, Rasht, Iran

Background: It is believed that environmental and genetic factors may beresponsible for autism. Methylenetetrahydrofolate reductase (MTHFR) and itsgene polymorphisms have been shown to be implicated as risk factors in autism.Objectives: To analyze MTHFR C677T polymorphism (rs1801133) in autisticpatients.Materials and Methods: This study was carried out in 2014 and 2015 innorthern Iran. One hundred and seventy-one male autistic patients and 198healthy males were included in this study. Autism was diagnosed according tothe Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSMIV)criteria. Each autism spectrum disorder (ASD) patient was also evaluatedby the Childhood Autism Rating Scale (CARS). All participants were tested forC677T polymorphism by using polymerase chain reaction-restriction fragmentlength polymorphism (PCR-RFLP) method.Statistical analyzes were performed using MedCalc version 12.1 by the χ2 testand logistic regression model. A value of p<0.05 was considered statisticallysignificant.Results: The mean age±SD of case and control groups was 13.5±2.7 and15.6±3.7 years. The mean±SD of CARS score was 36.2±1.7.The genotype frequencies of CC, TC, and TT in children with autism were50.9%, 45.6%, and 3.5%, respectively, and in control group were 54.5%,44.0%, and 1.5%, respectively (p> 0.05). The allele frequencies of C and T inchildren with autism were 73.0% and 27.0%, and in control group were 76.0%and 24.0%, respectively (p> 0.05).Conclusion: MTHFR C677T polymorphism is not associated with autism in apopulation in the north of Iran.

Methylenetetrahydrofolate Reductase; Autism Spectrum Disorders; Polymorphism, Genetic