HLA-DRB1 and systemic sclerosis: HLA-DRB1*1101, *1104, *1501, and *0802 (commonly associated with the dcSSc subset) show the amino acid sequence 67FLEDR71 in their β chain, whereas HLA-D Q β1 alleles *D301, *0302, *0401, *0402, *0601, and *0602 (commonly associated with SSc) show a 71TRAELDT77 motif on their β chain (29).