title: Association of HLA class II genes with systemic sclerosis in Spanish patients.
abstract: OBJECTIVE
  To examine the role of HLA-DRB1 and HLA-DQB1 alleles in the susceptibility to systemic sclerosis (SSc) and its clinical expression in a Spanish population.
  
  
  METHODS
  One hundred Spanish Caucasian patients with SSc and 130 controls were studied. Molecular HLA-DRB1 and HLA-DQB1 typing was performed by polymerase chain reaction (PCR) sequence-based typing and PCR sequence-specific oligonucleotide.
  
  
  RESULTS
  HLA-DRB1*11 was associated with genetic susceptibility to SSc, whereas HLA-DRB1*07 (HLA-DRB1*0701) showed a protective effect. A significant increase in the frequency of the DRB1*1104 allele was observed in patients with anti-topoisomerase I autoantibodies (anti-Topo I) while HLA-DRB1*01 and HLA-DQB1*05 alleles were significantly increased in patients with anti-centromere antibodies (ACA). The HLA-DRB1*11 allele was more frequent in patients with pulmonary fibrosis; however, no significant association with any HLA-DRB1 or DQB1 alleles was identified in patients with pulmonary arterial hypertension.
  
  
  CONCLUSIONS
  HLA alleles play a role in genetic susceptibility to SSc in Spanish patients. Some alleles are more prevalent in patients with pulmonary fibrosis and in patients with certain SSc-specific autoantibodies (anti-Topo I and ACA).
authors.affiliation: Internal Medicine Service, Immunohematology Service, Preventive Medicine Service, and Rheumatology Unit, Vall d'Hebron Hospital, Barcelona, Spain. cpsimeon@vhebron.net.
authors.forename: Carmen P
authors.initials: CP
authors.lastname: Simeón
authors.forename: Vicent
authors.initials: V
authors.lastname: Fonollosa
authors.forename: Carles
authors.initials: C
authors.lastname: Tolosa
authors.forename: Eduard
authors.initials: E
authors.lastname: Palou
authors.forename: Albert
authors.initials: A
authors.lastname: Selva
authors.forename: Roser
authors.initials: R
authors.lastname: Solans
authors.forename: Lluis
authors.initials: L
authors.lastname: Armadans
authors.forename: Estefania
authors.initials: E
authors.lastname: Moreno
authors.forename: Sara
authors.initials: S
authors.lastname: Marsal
authors.forename: Miquel
authors.initials: M
authors.lastname: Vilardell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D001323:Autoantibodies / Q000235:genetics / Q000276:immunology; D005260:Female; D005802:Genes, MHC Class II; D020022:Genetic Predisposition to Disease; D006683:HLA-DQ Antigens / Q000235:genetics / Q000276:immunology; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology; D059811:HLA-DRB1 Chains; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012595:Scleroderma, Systemic / Q000235:genetics / Q000276:immunology; D044465:White People / Q000235:genetics*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains