We also studied the association of CSF NLK in aMCI and AD patients with a positive biomarker status A+T+(N+), and we performed an exploratory study on the association of CSF NLK with CSF YKL-40, and the known Alzheimer CSF biomarkers total tau, phosphorylated tau, and Aβ42. The gene discussed is CHI3L1; the disease is Alzheimer disease.