title: Mediterranean and Amerindian MHC class II alleles are associated with multiple sclerosis in Mexicans.
abstract: OBJECTIVE
  Human leukocyte antigen (HLA)-DRB1, DQA1, DQB1 allele typing was performed in Mexicans Mestizos with multiple sclerosis (MS) to define the HLA class II alleles associated with the disease in this population.
  
  
  METHODS
  Patients (n = 51) diagnosed according to the Poser criteria and a group of 173 unrelated healthy subjects were studied. PCR-SSOP and PCR-SSP were used for genotyping.
  
  
  RESULTS
  Fifty five percent of the patients were females. The mean age at disease onset was 27 years. A relapsing-remitting disease was the most frequent type of MS (67%). A significant association of DRB1*0403 (OR = 5.68) with MS was shown. DRB1*0802 was also involved in susceptibility (OR = 2.41). An excess of DRB1*0802 homozygotes was observed in patients (P = 0.005), this genotype being in genetic equilibrium in controls.
  
  
  CONCLUSIONS
  Two novel class II associations are described in Mexicans with MS: DRB1*0403 and DRB1*0802. Both alleles share with DRB1*1501, valine-86 and negatively charged amino acids, in the DRB1-anchoring motif of pocket 4.
authors.affiliation: Department of Immunology & Immunogenetics, Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE), Secretary of Health, Mexico City, Mexico.
authors.forename: C
authors.initials: C
authors.lastname: Aláez
authors.forename: T
authors.initials: T
authors.lastname: Corona
authors.forename: L
authors.initials: L
authors.lastname: Ruano
authors.forename: H
authors.initials: H
authors.lastname: Flores
authors.forename: M
authors.initials: M
authors.lastname: Loyola
authors.forename: C
authors.initials: C
authors.lastname: Gorodezky
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D005006:Ethnicity / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D006683:HLA-DQ Antigens / Q000235:genetics; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D007197:Indians, Central American / Q000235:genetics*; D008297:Male; D019083:Mediterranean Region / Q000208:ethnology; D008800:Mexico; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000235:genetics*; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000235:genetics*
chemical_list: D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; C069050:HLA-DQA1 antigen; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D000949:Histocompatibility Antigens Class II