Indeed, several genes linked to the keratinization process (e.g., NCSTN, PSENEN, and GJB2), but also to autoinflammation (e.g., PSTPIP1, MEFV, MVK, NOD2, NLRP3, and IL1RN), have been reported in patients with HS and its syndromic forms, suggesting that both pathways are crucial in the pathogenesis of the disease [46]. This evidence concerns the gene PSTPIP1 and histiocytic sarcoma.