For example, individuals with loss-of-function mutations of the DPP1 gene develop prepubertal aggressive periodontitis, Papillon-Lefèvre syndrome (PLS) (24), or Haim-Munk syndrome (25), yet these patients do not exhibit marked immunodeficiency despite the near total loss of active granule-associated NSPs (26). This evidence concerns the gene CTSC and Papillon-Lefèvre syndrome.