ADAMTS1 and pachyonychia congenita: In regard to stage I PC patients, the percentages of ADAMTS1 and BNC1 DNA methylation were 87.5% and 62.5%, respectively; for stage IIa, the percentages were 77.8% and 55.6%, respectively; for stage IIb, the percentages were 90% and 65%, respectively; and for late-stage (III + IV), the percentages were almost 100%.