title: Evidence for a protective influence of blood group A phenotype on X-ray signs of ankylosing spondylitis in HLA-B27 positives.
abstract: A total of 148 cases of HLA-B27 positive cases of suspected early ankylosing spondylitis were investigated for the influence of ABH-phenotypes. The 70 patients sharing X-ray signs of the disease had a significantly lower frequency of the A-phenotype, the 78 X-ray negatives showed an A excess. The positive protective effect of phenotype A on the development of the disease in HLA-B27 positives is discussed.
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics*; D015235:HLA-B Antigens / Q000235:genetics*; D015796:HLA-B27 Antigen; D006801:Humans; D010641:Phenotype; D011859:Radiography; D013167:Spondylitis, Ankylosing / Q000097:blood* / Q000000981:diagnostic imaging
chemical_list: D000017:ABO Blood-Group System; D015235:HLA-B Antigens; D015796:HLA-B27 Antigen