TGFB1 and arthritic joint disease: Kotlarz D found that the TGF-β1 gene (c.328C/T, p.Arg110Cys) and (c.133C/T, p.Arg45Cys) is located in the sequence encoding the LAP structural domain.[61] Both loci are associated with immune dysregulation, which may lead to diseases such as arthritis, encephalopathy, inflammatory bowel disease, recurrent infections, and immunodeficiency.