Severe GBA1 variants drive the GBA1-PD clinical phenotype: implications for counselling and clinical trials
Elisa Menozzi, Sara Lucas Del Pozo, Jane Macnaughtan, Roxana Mezabrovschi, Sofia Koletsi, Pierfrancesco Mitrotti, Luca Gallo, Rosaria Calabrese, Marco Toffoli, Nadine Loefflad, Franco Valzania, Francesco Cavallieri, Valentina Fioravanti, Selen Yalkic, Naomi Limbachiya, Fabio Blandini, Micol Avenali, Anthony H.V. Schapira
Abstract
Variants in the GBA1 gene are the commonest genetic risk factor for Parkinson disease (PD). Genotype-phenotype correlations exist but with conflicting data. Here, we compared the clinical phenotype of 183 idiopathic PD (iPD) patients, 39 severe GBA1-PD, 24 mild GBA1-PD, and 55 risk GBA1-PD. Compared to iPD, we observed that only severe GBA1-PD patients had a distinctive, more several clinical profile, characterised by worse depression, hyposmia, cognitive dysfunction, and possibly constipation.