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

## TL;DR

A rare RAB39B gene mutation is linked to Parkinson's disease in an Italian family, with unique treatment approaches.

## Contribution

A novel RAB39B hemizygous variant is identified in a patient with Parkinsonism and intellectual disability.

## Key findings

- A new RAB39B mutation c.463C>T was found in a patient with early-onset Parkinsonism and intellectual disability.
- The mutation was also present in the patient's mother, who had late-onset Parkinson's disease.
- This expands the known RAB39B mutations associated with X-linked Parkinson's disease.

## Abstract

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.