HS syndromes in which genetic changes have been reported include PASH, PAPASH, and SAPHO syndromes; Braun-Falco et al. [76] first described two PASH families in which an increased number of CCCTG repeating in the promoter region of the PSTPIP1 (Proline-Serine-Threonine Phosphatase Interacting Protein 1) gene was found. This evidence concerns the gene PSTPIP1 and SAPHO syndrome.