Investigation of the relationship between sensory differences and prodinorphin gene polymophisms in children with autism spectrum disorder

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder characterized by repetitive behaviors, and deficiencies in social communication. Sensory symptoms, one of the diagnostic criteria of ASD, become manifest with different responses to smell, touch, visual or auditory inputs. The opioid system is thought to play a role in many processes such as social behavior, pain, addiction, reward, mood, cognition, and perception.In our study, we aimed to investigate the relationship between ASD, sensory differences and prodynorphin gene polymorphisms in children who received the diagnosis of ASD. Our study was performed with 45 children aged 3-7 years diagnosed with ASD, and 45 age and sex-matched healthy children as the control group. The parents of all children participating in the study were requested to complete Sociodemographic Data Form, Autism Behavior Checklist, and Dunn's Sensory Profile-Caregiver Questionnaire. The clinical severity of ASD patients was evaluated by the researcher using the Childhood Autism Rating Scale. Four ml of venous blood was drawn from all children participating in the study to investigate the prodynorphin gene polymorphisms. As a result of our study, any significant difference was not detected between the ASD and control groups in terms of prodynorphin gene polymorphisms. While there was no difference between the groups regarding the 'Sensory Processing Related to Endurance/ Tone' score, 'Low Endurance/Tone score and 'Immobility' scores, all other subtest scores were found to be significantly lower in the ASD group. However a significant difference was found in the number of children with the diagnosis of ASD demonstrating atypical performance in terms of genotype frequencies for the prodynorphin rs1022563 polymorphism in the subtests of 'Oral Sensory Processing' and 'Modulation of Visual Inputs Affecting Emotional Responses and Activity Level'