HLA-DRB1 and mixed connective tissue disease: 9 Paradowska-Gorycka Paradowska-Gorycka A A Stypinska Stypinska B B Olesinska Olesinska M M Association of HLA-DRB1 alleles with susceptibility to mixed connective tissue disease in Polish patients Association of HLA-DRB1 alleles with susceptibility to mixed connective tissue disease in Polish patients HLA.