title: Complement C4B-null alleles in Felty's syndrome.
abstract: C4A and C4B allotypes were compared in 20 patients with Felty's syndrome (FS), 52 patients with rheumatoid arthritis (RA), and 55 control subjects. Nineteen of the FS patients had HLA-DR4. A C4B-null allele was more frequent in the patients with FS (60%) than in either the RA patients (15%) or the control subjects (26%). Only the differences between patients with FS and those with RA remained statistically significant when DR4 positive subjects were compared. The C4B null allele may identify individuals within the rheumatoid population who are at risk of developing particular systemic complications.
authors.affiliation: University of Manchester, Rheumatic Diseases Centre, Hope Hospital, Salford, United Kingdom.
authors.forename: W
authors.initials: W
authors.lastname: Thomson
authors.forename: P A
authors.initials: PA
authors.lastname: Sanders
authors.forename: M
authors.initials: M
authors.lastname: Davis
authors.forename: J
authors.initials: J
authors.lastname: Davidson
authors.forename: P A
authors.initials: PA
authors.lastname: Dyer
authors.forename: D M
authors.initials: DM
authors.lastname: Grennan
mesh_terms: D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000235:genetics*; D003181:Complement C4 / Q000235:genetics*; D015934:Complement C4a; D015935:Complement C4b; D005258:Felty Syndrome / Q000235:genetics*; D005787:Gene Frequency; D006681:HLA-D Antigens / Q000235:genetics*; D006684:HLA-DR Antigens / Q000235:genetics*; D015804:HLA-DR4 Antigen; D006239:Haplotypes; D006801:Humans; D012307:Risk Factors
chemical_list: D003181:Complement C4; D006681:HLA-D Antigens; D006684:HLA-DR Antigens; D015804:HLA-DR4 Antigen; D015934:Complement C4a; D015935:Complement C4b