title: Letter: Low incidence of HLA-B27 in American Blacks with spondyloarthropathies.
mesh_terms: D016918:Arthritis, Reactive / Q000276:immunology*; D044383:Black People; D006680:HLA Antigens / Q000302:isolation & purification*; D006649:Histocompatibility Antigens / Q000302:isolation & purification*; D006801:Humans; D013167:Spondylitis, Ankylosing / Q000276:immunology*; D014481:United States / Q000208:ethnology; D044465:White People; D001741:Black or African American
chemical_list: D006680:HLA Antigens; D006649:Histocompatibility Antigens