The DEGAM guideline is much more cautious in the recommendation of cholinesterase inhibitors than the guideline of the DGN/DGPPN, and while memantine is recommended for Alzheimer's disease in the guideline of the DGN/DGPPN, the DEGAM only recommends it as an individual approach for therapy [20]. The gene discussed is BCHE; the disease is early-onset autosomal dominant Alzheimer disease.