Research has demonstrated the expression and distribution of NRG1 and ErbB kinases in the hippocampus of AD patients and in transgenic mice co-expressing AD-associated mutations of β amyloid precursor protein (APPK670N, M671L) and presenilin-1 (PS1M146L; Chaudhury et al., 2003). The gene discussed is PSEN1; the disease is Alzheimer disease.