title: HLA antigens and juvenile onset spondyloarthritides: negative association with non-B27 alleles.
abstract: OBJECTIVE
  To describe the association between HLA-B and HLA-DR genes and juvenile onset spondyloarthritides (SpA) in Mexicans.
  
  
  METHODS
  The study included 66 consecutive patients with SpA (45 with ankylosing spondylitis (AS) and 21 with undifferentiated SpA) and 99 non-related healthy controls. The HLA-A, -B and DR alleles were detected by the polymerase chain reaction with the sequence-specific primers technique. Statistical methods included the Mantel-Haenzel chi2 test, Fisher's exact test, and Woolf method for odds ratio (OR).
  
  
  RESULTS
  The frequency of HLA-B27 was significantly increased in the whole group (pC < 10(-3), OR = 53.0, aetiological fraction = 51%), particularly in AS (pC < 10(-3), OR = 67.42, aetiological fraction 57%). In contrast, the frequencies of HLA-B44, and HLA-B14 were significantly decreased. Also, a weak negative association HLA-DR5 (p < 0.05) was found.
  
  
  CONCLUSIONS
  Apart from an expected significant association between HLA-B27 and juvenile-onset SpA, particularly AS, we found negative associations with HLA-B44, B14, and DR5. There was also a trend for HLA-B15 and DR1 associations with SpA.
authors.affiliation: Dept. of Population Genetics, Centro de Investigación Biomédica del Noreste, Instituto Mexicano del Seguro Social, Mexico.
authors.forename: B
authors.initials: B
authors.lastname: Silva-Ramírez
authors.forename: G
authors.initials: G
authors.lastname: Vargas-Alarcón
authors.forename: J
authors.initials: J
authors.lastname: Granados
authors.forename: R
authors.initials: R
authors.lastname: Burgos-Vargas
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006680:HLA Antigens / Q000276:immunology*; D015796:HLA-B27 Antigen / Q000276:immunology; D006684:HLA-DR Antigens / Q000276:immunology; D006801:Humans; D008297:Male; D008800:Mexico; D025241:Spondylarthritis / Q000276:immunology*; D013167:Spondylitis, Ankylosing / Q000276:immunology
chemical_list: D006680:HLA Antigens; D015796:HLA-B27 Antigen; D006684:HLA-DR Antigens