SNCA and early-onset autosomal dominant Alzheimer disease: Both SNCA-140 and SNCA-126 downregulation and SNCA-98 overexpression have been reported in dementia with Lewy bodies and Alzheimer’s disease, while SNCA-112 is upregulated in dementia with Lewy bodies and downregulated in Alzheimer’s disease [27, 28, 24].