For example, kidney disease has been shown to alter the plasma levels of neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP), tau phosphorylated at threonine 181 (p-tau181), p-tau217, Aβ42 and Aβ40 measures, but the Aβ42/Aβ40 ratio is unaffected and the clinical performance of all the plasma markers does not seem to be significantly affected [57–60]. The gene discussed is GFAP; the disease is kidney disorder.