Abundance of drug transporters in the small intestine in APPswe/PSEN1dE9 (APP/PS1) transgenic mice [widely-used Alzheimer disease model, expressing a chimeric mouse/human amyloid precursor protein (Mo/HuAPP695swe) as well as a mutant human presenilin 1 (PS1-dE9)] mice, measured via quantitative targeted absolute proteomics (QTAP) was evaluated by Pan et al. [70]. This evidence concerns the gene PSEN1 and early-onset autosomal dominant Alzheimer disease.