PSTPIP2 and SAPHO syndrome: Notably, specific genetic variants, including mutations in the Proline-serine-threonine phosphatase interacting protein 2 (PSTPIP2) and Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) genes, have been implicated in the onset of SAPHO syndrome; however, these associations require further validation in larger studies (4).