A recent study reported that the levels of DHHC7 and DHHC21 are increased in the hippocampus of 3xTg-AD mice (a triple transgenic AD mouse model, expressing human gene mutants APPswe, PS1M146V, and tauP301L) and induce aberrant palmitoylation of key proteins that trigger Aβ aggregation in the brains of humans with AD [3, 30]. This evidence concerns the gene ZDHHC21 and Alzheimer disease.