Exploring the common genes involved in autism spectrum disorder and Parkinson's disease: A systematic review

Autism Spectrum Disorder (ASD) and Parkinson's disease (PD) are distinct neurodevelopmental disorders associated with distinct brain areas. ASD is characterized by delayed social communication skills and restricted repetitive behaviours. Conversely, PD is a progressive neurodegenerative disorder affecting basal ganglia, causing resting tremor, rigidity, postural instability, and bradykinesia. Both diseases share similarities in affected brain areas, including motor control and social behaviour. In both diseases, PARK2, SHANK3, SLC, RIT2, DRD2, and CD157/BST1 genes are involved by regulating synaptic function and dopamine neurons. Mutations in PARK2, an E3 ubiquitin ligase, can lead to dysfunctional mitophagy, causing the accumulation of damaged mitochondria and contributing to neuronal cell death, a hallmark of PD. PARK2 pathway disruptions have also been observed in some individuals with ASD, which are involved in tagging damaged or unwanted proteins for degradation, leading to the accumulation of misfolded or dysfunctional proteins that may contribute to neurodevelopmental abnormalities. PINK1 is crucial for maintaining mitochondrial quality and eliminating dysfunctional ones that produce reactive oxygen species (ROS). Mutations in this gene lead to damaged mitochondria and increased ROS production, contributing to neurodegeneration in dopamine-producing neurons. This review highlighted the various genes involved in pathogeneses of ASD and PD with their future implications.