A previous study of AD, mild cognitive impairment and control CSF62 used a similar pipeline to validate a panel of biomarkers in a single cohort with longitudinal CSF samples, and found four biomarkers that differentiated clinical AD from healthy controls, including YKL-40, Complement component C3, transthyretin and amyloid A4 protein. Here, CHI3L1 is linked to Alzheimer disease.