The Tg(PDGFB-APPSwInd)20Lms (MGI:3057148, here referred to as ‘J20’) mouse model is a transgenic animal that overexpresses mutant human APP protein (amyloid precursor protein), and is widely used as a model of amyloid deposition and pathogenesis in the study of Alzheimer’s disease (AD). The gene discussed is APP; the disease is early-onset autosomal dominant Alzheimer disease.