A similarenhancement of oligomer stability in heavy water was suggested fortransthyretin tetramer.49 Interestingly,it was recently found that the fibrillization of alpha-synuclein (theprotein responsible for Parkinson’s disease) proceeds faster in D2O than in water.40 This acceleration was attributed to enhanced protein–proteininteractions in D2O that facilitate the refolding of alpha-synuclein,which is required for initiating its fibrillization. This evidence concerns the gene SNCA and Parkinson disease.