title: Evidence that the low frequency antigen Orriss is part of the MN blood group system.
abstract: The low frequency antigen Orriss (Or) was found on the erythrocytes of a healthy blood donor. A subsequent family investigation showed Or to segregate independently of the Rh, Colton and Kidd blood group systems; however, it appeared to be inherited with the Ms gene complex. Studies carried out demonstrated that sialoglycoproteins (SGPs) extracted from Or+ erythrocytes specifically neutralize anti-Or and that all Or+ individuals tested carry an M antigen which is more resistant to trypsin treatment than the M antigen of Or- erythrocytes. These results lead to the conclusion that the Or antigen is found on a variant alpha-SGP and its presence renders this molecule more resistant to trypsin than normal.
mesh_terms: D000954:Antigens, Surface / Q000235:genetics*; D001788:Blood Grouping and Crossmatching; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes; D004912:Erythrocytes / Q000276:immunology; D006801:Humans; D007519:Isoantigens / Q000235:genetics / Q000276:immunology; D008951:MNSs Blood-Group System / Q000235:genetics / Q000276:immunology*; D008297:Male; D010375:Pedigree; D012795:Sialoglycoproteins / Q000032:analysis
chemical_list: D000954:Antigens, Surface; D000939:Epitopes; D007519:Isoantigens; D008951:MNSs Blood-Group System; D012795:Sialoglycoproteins