TNFAIP3 and Autoimmunity: In addition to RIPK1 variants, variants of proteins that can regulate RIPK1 ubiquitination and phosphorylation, such as variants in the TNFAIP3 gene, which encodes the protein A20, are linked with autoimmunity and inflammation, and likely also contribute to irregularities of RIPK1 function (74, 75).