APP and Alzheimer disease: It should be also noted that concurrently with the increase in levels of iAβ, the AβPP-independent pathway elevates the levels of AβPP intracellular domain, AICD that was shown to be capable of interference with various components of AD [162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177] but whose potential involvement in the disease remains to be fully elucidated (reviewed in [4,7]).