Primary Sjögren’s syndrome (pSS) is a chronic autoimmune disease with a dominance of immunological features such as hypergammaglobulinemia, B and T cell activation, autoantibody production mainly against ribonucleoproteins (anti-SSA/Ro and anti-SSB/La antibodies), low levels of C3 and C4 components of the complement system, rheumatoid factor (RF) and cryoglobulin production. This evidence concerns the gene TRIM21 and peeling skin syndrome.