RAB39B Related Parkinsonism in an Italian Family: A Unique Use of Advanced Therapies

Parkinson's disease (PD) is a neurodegenerative disorder that may sometimes be caused by deleterious genetic variants. Among them, RAB39B polymorphisms are known as rare causes of early‐onset PD associated with intellectual disability (Waisman's syndrome). Here we describe a 45‐year‐old white male affected by developmental delay, childhood onset intellectual disability, epilepsy, and PD who was treated with subthalamic deep brain stimulation and subcutaneous L‐DOPA infusion. Next Generation Sequencing analysis revealed a currently unknown pathogenic hemizygous sequence variant c.463C>T (NM_171998.4) in the RAB39B gene, confirmed also in the proband's mother, affected by late‐onset PD. This report expands the number of described RAB39B mutations in individuals with early‐ and late‐onset, X‐linked PD.