PSTPIP1 and pachyonychia congenita: Variants in GJB2 are more commonly associated with the Follicular Occlusion Triad (FO3) and Keratitis-Ichthyosis-Deafness syndrome (KID), KRT17 variants with the Follicular Occlusion Tetrad (FO4), KRT6A and KRT17 variants with Pachyonychia Congenita (PC), MEFV variants with PASH and PAPASH syndromes, OCRL variants with Dent Disease 2 (DD2), POFUT1 and POGLUT1 variants with Dowling Degos Disease (DDD), and PSTPIP1 variants with PASH and PAPASH syndromes.