GBA1 and Parkinson disease: Carriers for mutations in GBA1 and patients with GD have a lifetime relative risk of developing PD greater than that of the overall population, which depends on the age (for instance, the penetrance of PD in heterozygous carriers of GtBA1 mutations is estimated at 13.7% at the age of 60 and 29.7% at the age of 80) and on the the mutations (the odds ratios for PD in GBA1 mutation heterozygous ranged between 2.84 and 21.29 depending on the severity of the mutation) [9–12].