title: Gm allotypes in myasthenia gravis.
abstract: Gm typing and acetylcholine receptor antibody assay were performed on serum samples from 74 patients with myasthenia gravis (31 male, 43 female) and from 236 unrelated normal blood-donors. The haplotype Gm1,2,21 was significantly more common in patients with myasthenia gravis (relative risk = 3.24), especially those with thymoma (relative risk = 6.99). The frequency of haplotype Gm1,2,21 was further increased in patients with severe generalised myasthenia gravis (relative risk = 10.52). The frequency of Gm1,2,21 was also increased in patients with high acetylcholine receptor antibody titres (greater than 5 pmol/ml). The results indicate the presence of a pathogenic gene close to the IgG heavy-chain gene complex in the 6th chromosome in the patients with myasthenia gravis, especially those with thymoma.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000032:analysis; D002648:Child; D002675:Child, Preschool; D005260:Female; D006680:HLA Antigens / Q000235:genetics; D006801:Humans; D007126:Immunoglobulin Allotypes / Q000235:genetics*; D007074:Immunoglobulin G / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000235:genetics* / Q000276:immunology; D011950:Receptors, Cholinergic / Q000276:immunology; D012306:Risk; D013945:Thymoma / Q000235:genetics / Q000276:immunology; D013953:Thymus Neoplasms / Q000235:genetics / Q000276:immunology
chemical_list: D001323:Autoantibodies; D006680:HLA Antigens; D007126:Immunoglobulin Allotypes; D007074:Immunoglobulin G; D011950:Receptors, Cholinergic