title: C4 null genes in American whites and blacks with myositis.
abstract: The frequencies of C4A and C4B alleles were determined in 66 adults with myositis in relation to HLA class I and II. In whites with myositis, the C4A*Q0 allele occurred in 13/31 (47%) as compared to 25/101 (25%) normal controls (p = 0.08, relative risk = 2.7). Only 11/35 (31%) of black patients with myositis had a C4A*Q0 allele compared to 11/55 (20%) of controls (p = NS, RR = 1.8). Thus, the MHC class III genes do not appear to be the primary genetic risk factors for myositis in adults.
authors.affiliation: Department of Internal Medicine, University of Texas Medical School, Houston 77225.
authors.forename: J M
authors.initials: JM
authors.lastname: Moulds
authors.forename: C
authors.initials: C
authors.lastname: Rolih
authors.forename: R
authors.initials: R
authors.lastname: Goldstein
authors.forename: K F
authors.initials: KF
authors.lastname: Whittington
authors.forename: N B
authors.initials: NB
authors.lastname: Warner
authors.forename: I N
authors.initials: IN
authors.lastname: Targoff
authors.forename: M
authors.initials: M
authors.lastname: Reichlin
authors.forename: F C
authors.initials: FC
authors.lastname: Arnett
mesh_terms: D000483:Alleles; D044383:Black People / Q000235:genetics*; D002872:Chromosome Deletion; D003181:Complement C4 / Q000235:genetics*; D003882:Dermatomyositis / Q000208:ethnology / Q000235:genetics / Q000276:immunology; D005796:Genes; D006680:HLA Antigens / Q000032:analysis / Q000235:genetics; D006801:Humans; D009220:Myositis / Q000208:ethnology / Q000235:genetics* / Q000276:immunology; D010641:Phenotype; D014481:United States; D044465:White People / Q000235:genetics*; D001741:Black or African American
chemical_list: D003181:Complement C4; D006680:HLA Antigens