KIF5A and Alzheimer disease: Hares et al. (2017) evaluated the levels of KIF5A and KLC1 (mRNA relative to the neuronal density marker neuregulin). They observed a notable upregulation of KIF5A mRNA expression during Braak stages III-IV and V-VI (compared to stages I-II). The KLC1 mRNA levels exhibited a significant elevation in late Braak stage V-VI as opposed to the early stages, as assessed using the neurofibrillary tangle (NFT) scoring method (Braak and Braak, 1991). SNPs in KLC1 have no impact on KIF5A, while specific KIF5A SNPs (rs12368653 and rs4646536) are associated with decreased mRNA expression in AD.