APP and Alzheimer disease: In addition, in neuroblastoma with overexpression of APP, it was found that the S47 phosphorylation level of H4 was 1.89 times higher than that of the control group, and significant phosphorylation of H4 was also found in the brains of patients with mild cognitive impairment, suggesting that this histone phosphorylation may play a role in promoting the pathological development of AD (Chaput et al., 2016).