title: Mannose-binding lectin variant alleles and the risk of arterial thrombosis in systemic lupus erythematosus.
abstract: BACKGROUND
  Cardiovascular disease is an important complication in patients with systemic lupus erythematosus (SLE). Variant alleles of the mannose-binding lectin gene are associated with SLE as well as with severe atherosclerosis. We determined whether mannose-binding lectin variant alleles were associated with an increased risk of arterial thrombosis among patients with SLE.
  
  
  METHODS
  Mannose-binding lectin alleles were genotyped by means of a polymerase-chain-reaction assay in 91 Danish patients with SLE. Arterial and venous thromboses occurring after the diagnosis of SLE were assessed in a prospective study. Arterial and venous thromboses were confirmed by appropriate diagnostic methods.
  
  
  RESULTS
  Fifty-four patients had no mannose-binding lectin variant alleles (A/A genotype), 30 were heterozygous (A/O genotype), and 7 were homozygous (O/O genotype). During a median follow-up of 9.1 years, arterial thromboses (cerebral or myocardial infarction or leg embolus) developed in 6 of the 7 patients with the O/O genotype, as compared with 18 of the 84 patients with the other two genotypes (hazard ratio, 5.8; 95 percent confidence interval, 2.2 to 15.2; overall incidence, 26 percent). After correction for other known risk factors, the hazard ratio was 7.0 (95 percent confidence interval, 1.9 to 25.4). Venous thromboses, which occurred in 14 patients, were statistically unrelated to the mannose-binding lectin genotype.
  
  
  CONCLUSIONS
  Among patients with SLE, homozygosity for mannose-binding lectin variant alleles is associated with an increased risk of arterial thrombosis. The risk of venous thrombosis is not increased, indicating that mannose-binding lectin has a specific role in providing protection against arterial thrombosis.
authors.affiliation: Department of Rheumatology, Bispebjerg Hospital, Copenhagen, Denmark.
authors.forename: Tommy
authors.initials: T
authors.lastname: Øhlenschlaeger
authors.forename: Peter
authors.initials: P
authors.lastname: Garred
authors.forename: Hans O
authors.initials: HO
authors.lastname: Madsen
authors.forename: Søren
authors.initials: S
authors.lastname: Jacobsen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D017153:Antibodies, Anticardiolipin / Q000097:blood; D005260:Female; D005838:Genotype; D006801:Humans; D015994:Incidence; D008180:Lupus Erythematosus, Systemic / Q000150:complications* / Q000235:genetics; D008297:Male; D037601:Mannose-Binding Lectin / Q000235:genetics*; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011446:Prospective Studies; D012307:Risk Factors; D013927:Thrombosis / Q000209:etiology / Q000235:genetics*
chemical_list: D017153:Antibodies, Anticardiolipin; D037601:Mannose-Binding Lectin