An age-related decrease in phosphatase levels in neural tissues has been implicated in Alzheimer’s disease (Sontag and Sontag, 2014), and PP2A has been shown to decrease in neural tissues with age (Veeranna et al., 2011), suggesting that declining PP2A activity could contribute to the defect we observed. This evidence concerns the gene PTPA and early-onset autosomal dominant Alzheimer disease.