MYO5B and Alzheimer disease: MYO5B is a member of the class V myosins participating in intracellular transport.47,48 Another member of the class V myosins, MYO5C, showed an association with late-onset AD based on its gene expression level.49 Despite SNP-smoking interactions being identified for GDF3 and MYO5B, our validation cohort's lack of smoking data precluded replicating these findings.