(1) MCI criteria according Petersen et al. (1999), or any other clearly defined criteria; (2) AD criteria according NINCDS–ADRDA and DSM-IV; (3) information regarding the follow-up period for MCI patients; (4) baseline levels of T-tau and/or p-tau and/or Aβ42 for MCI that will progress to AD; (5) sensitivity and specificity values. The gene discussed is MAPT; the disease is Alzheimer disease.