Although the association between mutations in GBA1 and parkinsonism is well established, most GBA1 mutation carriers never develop parkinsonism, implicating the contribution of other genetic, epigenetic, and/or environmental modifiers.
Thus, in patients with GBA1-associated parkinsonism, astrocytes appear to play a role in α-synuclein accumulation and processing, contributing to neuroinflammation.
Twenty-nine of 109 probands with autosomal-recessive inheritance of parkinsonism (26.6%) were found to carry mutations in Parkin, PINK1, GBA, or HTRA2.
In this review, we discuss evidence linking autophagic dysfunction to the pathophysiology of GD and GBA1-linked parkinsonism and focus more specifically on studies performed recently in iPSC-derived neurons.
The discovery of a link between mutations in GBA1, encoding the lysosomal enzyme glucocerebrosidase, and the synucleinopathies directly resulted from the clinical recognition of patients with Gaucher disease with parkinsonism.
We review the literature of genetic PD autopsies from cases with molecularly confirmed PD or parkinsonism and summarize main findings on SNCA (n = 25), Parkin (n = 20, 17 bi-allelic and 3 heterozygotes), PINK1 (n = 5, 1 bi-allelic and 4 heterozygotes), DJ-1 (n = 1), LRRK2 (n = 55), GBA (n = 10 Gaucher disease patients with parkinsonism), DNAJC13, GCH1, ATP13A2, PLA2G6 (n = 8 patients, 2 with PD), MPAN (n = 2), FBXO7, RAB39B, and ATXN2 (SCA2), as well as on 22q deletion syndrome (n = 3).
Because GBA1 mutations are the most common genetic risk factor for Parkinson disease, dopaminergic neurons were generated from iPSC lines derived from patients with Gaucher disease with and without parkinsonism.
Our findings in a representative series of index cases from families with ADPD emphasize the important contribution of LRRK2 G2019S and GBA (L444P and N370S) mutations to parkinsonism in Brazilian families.
Therefore, the current review focuses on α-syn and GCase, and it provides some new thoughts that may be helpful for understanding the α-syn-GCase interaction and unraveling the exact mechanism underlying GBA-associated parkinsonism.
In this review, we (i) outline how GBA was identified as a genetic risk factor for Parkinsonism, (ii) present clinical characteristics of GBA-associated Parkinsonism, (iii) discuss possible mechanisms of the underlying pathogenesis in GBA-associated Parkinsonism, and (iv) provide an outlook on potentially new areas of research and treatment that arise from this important discovery.
We measured dopamine synthesis with (18)F-fluorodopa positron emission tomography, and resting regional cerebral blood flow with H(2)(15)O positron emission tomography in the wakeful, resting state in four study groups: (i) patients with Parkinson disease and Gaucher disease (n = 7, average age = 56.6 ± 9.2 years); (ii) patients with Parkinson disease without GBA mutations (n = 11, 62.1 ± 7.1 years); (iii) patients with Gaucher disease without parkinsonism, but with a family history of Parkinson disease (n = 14, 52.6 ± 12.4 years); and (iv) healthy GBA-mutation carriers with a family history of Parkinson disease (n = 7, 50.1 ± 18 years).