Previous studies have reported conflicting results regarding the association of the Q7R polymorphism in the Saitohin gene with late-onset Alzheimer disease (AD). Given that AD is a tauopathy but no mutations or polymorphisms in Tau have been consistently associated with AD, and that Saitohin is nested in intron 9 of Tau and shares a similar expression pattern, we tested this association in 690 multiplex AD families and in a case-control sample (903 patients and 320 controls). We found no evidence of significant association of this polymorphism with risk of AD using family-based and case-control tests of association.