To investigate whether the binding epitope represents a major difference between IgG1 and IgG4 anti-Dsg1 autoantibodies, serum samples of a cohort of 53 PF patients admitted to Rui Jin Hospital, Shanghai, China, were analyzed for the total levels and subclasses of IgG anti-Dsg1 autoantibodies (Supplementary file 1d). The gene discussed is DSG1; the disease is pemphigus foliaceus.