NEFL and Parkinson disease: Additionally, researchers have reported that NfL is elevated in mouse models of Huntington’s disease, amyotrophic lateral sclerosis, Parkinson’s disease, Alzheimer’s disease, and Gaucher disease and that both CSF and blood levels of NfL are convincing and useful markers for monitoring disease progression and severity (Bacioglu et al., 2016; Loeffler et al., 2020; Soylu-Kucharz et al., 2017).