ARPP21 and Alzheimer disease: The biological functions of these overlapping proteins were mainly divided into the GO categories of development (Mrpl24, Fat4, Ints7, Trip13 and Bag1), metabolism (Mc4-r and Arpp21), cancer (Fam107b, Ddr1 and Lpp), cell cycle (Dcun1d3), and associated with Alzheimer’s disease & Parkinson’s disease (Ncapd2) (Fig. 5d).