Diagnostic follow-up of the A-MCI group revealed that 10 out of 38 patients received a clinical diagnosis of dementia or Parkinson disease later on; these neurodegenerative diseases have probably – as likely often the case in A-MCI – raised the NfL levels in the A-MCI group at baseline, making them indistinguishable from the levels in the A + MCI group. The gene discussed is NEFL; the disease is Parkinson disease.