Malfunction of the initiation factor EIF2B3 are known to make cells less tolerant to endoplasmic reticulum stress [31], and high cellular activity of the propyl endopeptidase (PREP) has been hypothesized to lead to an aggregation of α-synuclein, thus being a contributing factor for neurodegenerative diseases [31]. This evidence concerns the gene EIF2B3 and neurodegenerative disease.