A different perspective on Alzheimers is revealed by a mouse study that has found that APP possesses ferroxidase activity similar to ceruloplasmin, facilitating iron export through interaction with ferroportin; it seems that this activity is blocked by zinc trapped by accumulated Aβ in Alzheimers.  It has been shown that a single nucleotide polymorphism in the 5'UTR of APP mRNA can disrupt its translation.
The hypothesis that APP has ferroxidase activity in its E2 domain and facilitates export of Fe(II) is possibly incorrect since the proposed ferroxidase site of APP located in the E2 domain does not have ferroxidase activity.
As APP does not possess ferroxidase activity within its E2 domain, the mechanism of APP-modulated iron efflux from ferroportin has come under scrutiny. One model suggests that APP acts to stabilize the iron efflux protein ferroportin in the plasma membrane of cells thereby increasing the total number of ferroportin molecules at the membrane. These iron-transporters can then be activated by known mammalian ferroxidases (i.e. ceruloplasmin or hephaestin).