PDIA4 and diabetes mellitus: Closer analysis revealed that 58% of the Pdia4−/−Leprdb/db mice whose PBG was 137 mg/dl by 24 weeks of age, were diabetes‐free (Pdia4−/−Leprdb/db, Appendix Fig S2E) compared to the rest (42%) which exhibited slight diabetes with PBG around 340 mg/dl (Pdia4−/−Leprdb/db, Appendix Fig S2E).