title: Prevalence of Autoantibodies and HLA DR, DQ in Type 1 Diabetes Mellitus.
abstract: BACKGROUND
  Type I diabetes Mellitus (T1DM) is caused by autoimmune destruction of β-cells of pancreas. Two forms of T1DM are known called as 1A (autoimmune) and 1B (idiopathic).
  
  
  OBJECTIVE
  Aim was to study the prevalence of Anti-TTG IgA, Anti-TPO, GADA, ZnT8 and IA-2 autoantibodies and HLA DR and DQ genes and its diagnostic value in T1DM.
  
  
  METHODS
  Thirty four T1DM patients, 59 type 2 diabetes mellitus (T2DM) patients and 28 healthy controls were included in study. Antibodies levels were estimated by ELISA and HLA typing was performed by SSP-PCR method.
  
  
  RESULTS
  The prevalence of various autoantibodies in T1DM were Anti-TTG 14.7%, Anti-TPO 17.65%, GADA 38.23%, ZnT8 11.76% and IA-2 5.88%. Only GADA and ZnT8 were significantly positive in T1DM. GADA (66.67%) and ZnT8 (33.33%) positivity was more in patients below 15 years age while levels of other antibodies were higher after 15 years age. All autoantibodies were detected in higher frequency in T1DM than in T2DM and controls. HLA DR and DQ typing showed highly significant increase in DRB1*0301 (61.76%, p=0.00) and DQB1*0201 (64.71%, p=0.00) in T1DM. Subjects with HLA DRB1*0301 and DQB1*0201 had 80-100% positive prevalence of GADA, ZnT8, IA-2, Anti-TTG and Anti-TPO autoantibodies.
  
  
  CONCLUSIONS
  Combination of GADA antibody with DRB1 and DQB1 estimation improved diagnosis of T1A than insulin antigen specific antibodies alone.
authors.affiliation: Research Scholar, Department of Pathology, Institute of Medical Sciences, Banaras Hindu University , Varanasi, UP, India .
authors.forename: Shailja
authors.initials: S
authors.lastname: Singh
authors.affiliation: Professor and Incharge, UGC Advanced Immunodiagnostic Training and Research Centre, Department of Pathology, Institute of Medical Sciences, Banaras Hindu University , Varanasi, UP, India .
authors.lastname: Usha
authors.affiliation: Junior Resident, Department of Pathology, Institute of Medical Sciences, Banaras Hindu University , Varanasi, UP, India .
authors.forename: Gyanendra
authors.initials: G
authors.lastname: Singh
authors.affiliation: Professor, Department of Endocrinology, Institute of Medical Sciences, Banaras Hindu University , Varanasi, UP, India .
authors.forename: Neeraj Kumar
authors.initials: NK
authors.lastname: Agrawal
authors.affiliation: Professor, Department of Nephrology, Institute of Medical Sciences, Banaras Hindu University , Varanasi, UP, India .
authors.forename: Rana Gopal
authors.initials: RG
authors.lastname: Singh
authors.affiliation: Service Senior Resident, Department of Pathology, Institute of Medical Sciences, Banaras Hindu University , Varanasi, UP, India .
authors.forename: Shashi Bhushan
authors.initials: SB
authors.lastname: Kumar
keywords: Autoantibody; HLA-DQ alleles; HLA-DR alleles; Type 1 Diabetes; Type 2 Diabetes