The PARK2 gene (OMIM*602544) is one of neurodevelopmental genes that was originally discovered as one of the causes of early-onset Parkinson disease (PD) [13] and was subsequently reported to be associated with schizophrenia [14], ASD [15], and attention-deficit/hyperactivity disorder (ADHD) [16]. This evidence concerns the gene PRKN and Parkinson disease.