DSG1 and acquired polycythemia vera: In fact, although the majority of anti-Dsg3 IgG autoantibodies in PV did not cross-react with Dsg1, in mucocutaneous-type PV, with both anti-Dsg1 and anti-Dsg3, autoantibodies mapping results from this approach, may be less reliable, because of the sequence homology of two cadherins.