When specificity was fixed at 100%, the sensitivity for PC in the biopsy sample set was 95.8% (SLC18A2), 81.6% (HAPLN3), 79.2% (CCDC181), 77.1% (GSTP1), 75.0% (MOB3B), 70.8% (GAS6), 64.6% (AOX1), 54.2% (KLF8), 29.2% (GABRE), and 20.8% for PSA. The gene discussed is CCDC181; the disease is pachyonychia congenita.