title: Age-of-onset related HLA-DQA1 genetic heterogeneity of insulin-dependent diabetes mellitus.
abstract: OBJECTIVE
  To clarify whether there is an association of insulin-dependent diabetes mellitus (IDDM) susceptibility with HLA-DQA1 locus in adult-onset IDDM.
  
  
  METHODS
  Possible heterogeneity in immunogenetic aspects was investigated by comparing the findings on relationship between HLA-DQA1 52 Arg(+) and IDDM predisposition in three groups with different ages of IDDM onset (group A 14 years, group B 15-30 years, group C > 31 years).
  
  
  RESULTS
  The frequency of HLA-DQA1 52 Arg(+) in group A (87.5%) was higher than that in control (53.9%, P < 0.05) and in group B and C (P < 0.05). The frequency of HLA-DQA1 52 Arg(+)/Arg(+) phenotype in group A (75%) was higher than that in group C (23.1%, P < 0.05).
  
  
  CONCLUSIONS
  The contribution of HLA-DQA1 52 arginine to IDDM susceptibility is heterogeneous. Further study is necessary to clarify the immunogenetic entity of IDDM.
authors.affiliation: Department of Endocrinology, Memorial Hospital, Sun Yat-Sen University of Medical Sciences, Guangzhou.
authors.forename: H
authors.initials: H
authors.lastname: Cheng
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: Z
authors.initials: Z
authors.lastname: Fu
authors.forename: T
authors.initials: T
authors.lastname: Yan
mesh_terms: D000328:Adult; D017668:Age of Onset; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000276:immunology; D004198:Disease Susceptibility; D005260:Female; D018740:Genetic Heterogeneity; D006683:HLA-DQ Antigens / Q000235:genetics*; D059848:HLA-DQ alpha-Chains; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; C069050:HLA-DQA1 antigen