*Older immunization: past Epstein-Barr Virus infection. EBV: Epstein-Barr virus, VCA: viral capsid antigen, CMV: cytomegalovirus, Ag: antigen, Ac: anticorps, ENA: extractable nuclear antigen, RNP: ribonucleoprotein, SSA: Sjögren's syndrome-related antigen A autoantibodies, SSB: Sjögren's syndrome-related antigen B autoantibodies. This evidence concerns the gene ENAH and Epstein-Barr virus infection.