FOLR1 and neurodegenerative syndrome due to cerebral folate transport deficiency: Some patients with cerebral folate deficiency (CFD) have been reported to have mutations in the folate receptor 1 (FOLR1) gene (MIM *136430) with extremely low levels of 5-MTHF in CSF (Cario et al. 2009; Delmelle et al. 2016), but we did not find any mutation in this gene in this proband.