This is reminiscent of increased copy number of the APP gene (which encodes amyloid precursor protein and is causal for Alzheimer’s disease [Sleegers et al., 2006]) and of the SNCA gene (which encodes α-synuclein and is causal for Parkinson’s disease [Singleton et al., 2003]). The gene discussed is SNCA; the disease is early-onset autosomal dominant Alzheimer disease.