The mechanism underlying the parallel changes in Aβ and p75NTR-ECD remains unclear; however, p75NTR-ECD can bind with Aβ,33 and both full-length p75NTR and p75NTR-ECD affect Aβ metabolism.3, 9 Thus, these two events may be interdependent in AD pathogenesis. The gene discussed is NGFR; the disease is Alzheimer disease.