TNFAIP3 mutations, such as Arg87Ter, Val489Aal fs7, Gln490Ter, are His577Alafs95, were related to BD-like symptoms and type 1 (T1D) diabetes, suggesting that A20 haploinsufficiency may be related to the onset of diabetes. The gene discussed is TNFAIP3; the disease is diabetes mellitus.