GBA1 and Parkinson disease: All the centers screened at least two mutations, N370S and L444P, and found that 15% of the PD patients carried GBA mutations compared with 3% of the controls among the Ashkenazi Jewish patients; 3% of the PD patients carried GBA mutations compared with 1% of the controls among non-Ashkenazi patients (Sidransky et al., 2009).