In the proliferating AD cells Id2 has been found to be 20-fold more expressed than in the AI cells (together with N-Myc, which would support Id2 being an effector of N-Myc [115, 245]), and it is suggested to support proliferation by antagonizing the TGFβ/Smad2/3 pathway. The gene discussed is MYCN; the disease is Alzheimer disease.