Parkinson's disease in patients and obligate carriers of Gaucher disease

Background: Gaucher disease is an autosomal recessive disorder caused by glucocerebrosidase gene mutations. Accumulating evidence from several Parkinson's disease cohorts of varying ethnicities suggests that glucocerebrosidase mutations even in the heterozygous state (carriers) may be a susceptibility factor for Parkinson's. Very few studies have analyzed the frequency of Parkinson's in carriers and individuals with Gaucher disease. Objective: To determine frequency of Parkinson's in patients with Gaucher disease and obligate carriers of glucocerebrosidase mutations and compare it with a control group. Methods: A questionnaire was completed by 100 Ashkenazi Jewish Gaucher patients followed at our center and 109 ethnicity-matched controls with no personal or family history of Gaucher disease. Results: Frequency of Parkinson's was higher in Gaucher patients (8/100) than in controls (0/109; P = 0.0024). Frequency of Parkinson's in obligate carriers (11/200) was higher than controls (6/218), but the difference was not statistically significant (P = 0.215). Average age of onset of Parkinson's was earlier in Gaucher patients (57.2) than the general population and in obligate carriers (60) when compared with controls (76.8; P = 0.01). The L444P genotype was more frequent in Gaucher patients who reported a parent with Parkinson's (36.40%) than those who did not (4.50%). Conclusion: Our study suggests that the risk for developing Parkinson's may be higher in affected versus carriers of glucocerebrosidase mutations and suggests that L444P may pose a higher risk of developing Parkinson's than other mutations. It also confirms previous findings that the age of onset of Parkinson's associated with glucocerebrosidase mutations is earlier than in the general population.