A PARK7 Mutation-Induced Early-Onset Parkinson's Disease in a Moroccan Family: Expanding the Geographic Spectrum

Background: Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor and nonmotor symptoms, with a significant genetic component. Early-onset Parkinson's disease (EOPD), manifesting before age 45, is often linked to mutations in genes such as PARK2, PINK1, and PARK7, the latter coding for the protein DJ-1. Objective: We present the first reported cases of EOPD carrying a previously undescribed homozygous PARK7 mutation, p.Thr110Pro. Methods: Whole exom sequencing was performed on two inbred Moroccan siblings with early-onset Parkinson's disease (EOPD). Detailed clinical assessments, including neurological evaluations and cognitive testing, were conducted to understand the clinical presentation of the patients. Genetic analysis was also carried out to examine their genetic background. Therapeutic responses to treatments were monitored to assess the effectiveness of management strategies. Results: The sequencing revealed that both siblings carried the homozygous PARK7 mutation, p.Thr110Pro. Both siblings presented with typical EOPD features, including motor and non-motor symptoms. The patients both presented with cognitive impairment, with the male sibling exhibiting more pronounced symptoms. He also developed compulsive behaviors, which underscore the varied clinical presentations and therapeutic responses associated with this genetic variant. Conclusion: This case study expands the genetic and geographic diversity of PD presentations, highlighting cognitive and behavioral challenges and variable therapeutic outcomes. It underscores the necessity for genetic screening and individualized management strategies for patients with PD.