title: HLA-DRB1*08 allele may help to distinguish between type 1 diabetes mellitus and type 2 diabetes mellitus in Mexican children.
abstract: BACKGROUND
  It may be difficult to distinguish type 1 diabetes mellitus (T1DM) from type 2 diabetes mellitus (T2DM) in the pediatric population. Autoantibodies may help to differentiate both types of diabetes, but sometimes these are positive in patients with T2DM and negative in patients with T1DM. The human leukocyte antigen (HLA)-DR genotype has been associated with T1DM and with T2DM only in adults and in determined cases.
  
  
  OBJECTIVE
  To determine the differences in HLA class II allele frequencies in Mexican children with T1DM and T2DM.
  
  
  METHODS
  We included 72 children with T1DM, 28 children with T2DM, and 99 healthy controls. All were Mexican, and diabetes was diagnosed according to the clinical and laboratory criteria established by the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. The HLA-DRB1 typing was performed using polymerase chain reaction-sequence-specific oligonucleotide probe and polymerase chain reaction sequence-specific primers.
  
  
  RESULTS
  We found an increased frequency of HLA-DRB1*08 and a decreased frequency of HLA-DRB1*04 in the group with T2DM vs. T1DM [p = 0.0001, odds ratio (OR) = 10.58, 95% confidence interval (CI) = 3-40.8 and p = 0.0006, OR = 0.24, 95% CI = 0.11-0.53, respectively]. No significant differences were found between HLA-DRB1 alleles in T2DM vs. controls. In the group with T1DM, there was a significantly increased frequency of the HLA-DR4 and HLA-DR3 alleles relative to controls (p = 0.0000001, OR = 3.59, 95% CI = 2.2-5.8 and p = 0.00009, OR = 4.66, 95% CI = 2.1-10.3, respectively).
  
  
  CONCLUSIONS
  There are significant differences in the HLA profile in Mexican children with T1DM and T2DM. HLA typing could play a role in the differentiation between both types of diabetes in this population.
authors.affiliation: Department of Pediatric Endocrinology, Hospital Infantil de México, Mexico City, Mexico.
authors.forename: Ana L
authors.initials: AL
authors.lastname: Rodríguez-Ventura
authors.forename: Jesus K
authors.initials: JK
authors.lastname: Yamamoto-Furusho
authors.forename: Ninel
authors.initials: N
authors.lastname: Coyote
authors.forename: Luis M
authors.initials: LM
authors.lastname: Dorantes
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Ruiz-Morales
authors.forename: Gilberto
authors.initials: G
authors.lastname: Vargas-Alarcón
authors.forename: Julio
authors.initials: J
authors.lastname: Granados
mesh_terms: D000293:Adolescent; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D006684:HLA-DR Antigens / Q000235:genetics*; D059811:HLA-DRB1 Chains; D006801:Humans; D008297:Male; D008800:Mexico
chemical_list: D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains