KLK6 and Alzheimer disease: Neurogranin (NRG), TAR DNA-binding protein 43 (TDP43), chitinase 3-like 1 (YKL40, cartilage glycoprotein-39), and kallikrein 6 (KLK6) are often found in classical AD and other dementias [42,43,44,45,46,47,48,49].