BACE1 and neurodegenerative disease: In light of this, we suggest that although the level of association detected in this study may be due to increased type I errors in multiple comparisons, the BACE1 rs638405 polymorphism is worthy of further investigation in PD, as it provides both a novel genetic link to the observed overlap in the amyloid pathology of PD and AD and increases the number of neurodegenerative diseases that this variant is associated with.