The absence of anti‐BP180/230 antibodies, which are typically elevated in bullous pemphigoid, contrasted with elevated anti‐desmoglein 1/3 antibodies (anti‐Dsg1: 171 U/mL; anti‐Dsg3: 172 U/mL), confirming the characteristic autoantibody profile of PNP. This evidence concerns the gene COL17A1 and bullous pemphigoid.