While TGFβ and TGFβ-receptor signaling has been studied extensively in the context of AD and neuroinflammation [25, 26], and BMP9/GDF2 has been identified as a regulator of cholinergic neuronal development [27], Activin receptor signaling and GDFs have not been studied in AD. This evidence concerns the gene TGFB1 and Alzheimer disease.