ADAM9 and pachyonychia congenita: In total it was found that, of the 383 differentially expressed genes found in PBMCs of PC patients, only 4 (ADAM9, IMP3, BTG2, and G6PD) were also shown to be differentially expressed in PC primary tissues, with 2 (ADAM9 and BTG2) being differentially expressed in the same direction (0.5% commonality) [30].