PARK2 Microdeletion or Duplications Have Been Implicated in Different Neurological Disorders Including Early Onset Parkinson Disease

The PARK2 gene is located on 6q26, encodes ubiquitin-E3- ligase, and is a transcriptional repressor of p53. It contains 12 exons. PARK2 copy number variants has been reported in various types of neurodevelopmental disorders, namely schizophrenia, Parkinson's disease (PD), autism spectrum disorder (ASD), and attention-deficit/hyperactivity disorder (ADHD). In this retrospective study, nine cases (five with microdeletion and four with microduplication) are reported with 6q26 deletion disrupting the PARK2 gene. Microdeletion sizes ranged between 215 Kb and 356 Kb, and duplication between 279 Kb and 726 Kb. These were present within the exons 7-10. Family follow up with FISH probes revealed paternal inheritance in two cases, maternal in two cases, and de novo origin in one case. Our results support previous studies showing that patients with PARK2 CNVs involving exons 5-12 might be more deleterious and cause a unique syndrome. Comprehensive analysis of additional case studies is needed to have a full characterization of this neurological disorder syndrome.