title: HLA-B27 subtypes in patients with ankylosing spondylitis (As) in Colombia.
abstract: OBJECTIVE
  We investigated the distribution of HLA-B27 subtypes in patients with ankylosing spondylitis (AS) belonging to two ethnic groups of Colombia.
  
  
  METHODS
  PCR-SSOs was used to detect the polymorphism in exons 2 and 3 of HLA-B27 in two groups of patients: 39 Mulattos and 20 Mestizos. Fifty-nine of them suffered of ankylosing spondylitis (AS), including two patients with ankylosing spondylitis plus anterior uveitis (AU). Only two out of eight HLA-B27 subtypes studied (B*2701-B*2708) were found.
  
  
  RESULTS
  The distribution of these alleles in the whole population was: B*2705: 87.1% and B*2702: 12.8% in the Mulattos group; 80% were B*2705 and 20% B*2702 in Mestizos group. The distribution of HLA-B27 subtypes was: 84.74% of patients with AS were B*2705 and 15.26% B*2702.
  
  
  CONCLUSIONS
  There was no significant difference in the distribution of HLA-B27 subtypes among the patients ethnic groups studied. Other authors have shown that B*2705, B*2702 and B*2704, the more frequent subtypes, are equally associated to the disease. Although population studies need to be done to analyze the distribution of subtypes between patients and controls, the low frequency of HLA-B27 within the normal population does not permit to do a representative number of controls; our results suggest that HLA-B*2705 and HLA-B*2702 are the subtypes more frequently associated with AS in patients from the two more prevalent patients ethnic groups in Colombia.
authors.affiliation: Instituto de Investigaciones Inmunológicas, Universidad de Cartagena, Colombia.
authors.forename: B
authors.initials: B
authors.lastname: Martínez
authors.forename: L
authors.initials: L
authors.lastname: Caraballo
authors.forename: M
authors.initials: M
authors.lastname: Hernández
authors.forename: R
authors.initials: R
authors.lastname: Valle
authors.forename: M
authors.initials: M
authors.lastname: Avila
authors.forename: A
authors.initials: A
authors.lastname: Iglesias Gamarra
mesh_terms: D000483:Alleles; D001327:Autoimmune Diseases / Q000453:epidemiology / Q000235:genetics*; D044383:Black People / Q000235:genetics; D003105:Colombia / Q000453:epidemiology; D005006:Ethnicity / Q000235:genetics; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D015796:HLA-B27 Antigen / Q000032:analysis / Q000145:classification / Q000235:genetics*; D006801:Humans; D007199:Indians, South American / Q000235:genetics; D008393:Marriage; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D013167:Spondylitis, Ankylosing / Q000453:epidemiology / Q000235:genetics*; D014606:Uveitis, Anterior / Q000453:epidemiology / Q000235:genetics; D044465:White People / Q000235:genetics
chemical_list: D015796:HLA-B27 Antigen