GFAP and neurodegenerative disease: In this study, we quantified levels of four neurodegenerative disease-related proteins, neurofilament light (NfL), total tau (t-tau), glial fibrillary acidic protein (GFAP) and YKL-40 in matched CSF, plasma and saliva samples from Huntingtin (HTT) gene-positive individuals (n = 21) using electrochemiluminescence assays.