These combined CTSB KO data in different hAβPP models are consistent with the hypothesis that CTSB participates in regulating Aβ produced from hAβPP with the Wt β-secretase site representing the major sporadic AD population, but not from hAβPP with the Swe mutant β-secretase site that represents a minor percentage of AD. The gene discussed is CTSB; the disease is Alzheimer disease.