title: Importance of Zinc Transporter 8 Autoantibody in the Diagnosis of Type 1 Diabetes in Latin Americans.
abstract: There is a scarcity of data of zinc transporter-8 autoantibody (ZnT8A) on mixed populations such as Brazilian. Therefore, we evaluated the relevance of ZnT8A for type 1 diabetes (T1D) diagnosis and the role of ZnT8 coding gene (SLC30A8) in T1D predisposition. Patients with T1D (n = 629; diabetes duration = 11 (6-16) years) and 651 controls were genotyped for SLC30A8 rs16889462 and rs2466295 variants (BeadXpress platform). ZnT8 triple antibody was measured by ELISA; glutamic acid decarboxylase (GAD65A) and protein tyrosine phosphatase (IA-2A) autoantibodies by radioimmunoassay.
  
  
  
  Znt8A was detected in 68.7% of recent-onset T1D patients and 48.9% of the entire patient cohort, similar to GAD65A (68.3% and 47.2%) and IA-2A (64.8% and 42.4%) positivities respectively. ZnT8A was the only antibody in 8.4% of patients. Znt8A and IA2A frequencies and titers were independent of gender and ethnicity, whereas GAD65A titers were greater in females. The diabetes duration-dependent decline in ZnT8A frequency was similar to GAD65A and IA-2A. The SLC30A8 rs2466293 AG + GG genotypes were associated with T1D risk in non-European descents (56.2% × 42.9%; p = 0.018), and the GG genotype with higher ZnT8A titers in recent-onset T1D: 834.5 IU/mL (711.3-2190.0) × 281 IU/mL (10.7-726.8); p = 0.027. Conclusion ZnT8A detection increases T1D diagnosis rate even in mixed populations. SLC30A8 rs2466293 was associated with T1D predisposition in non-European descents.
authors.affiliation: Laboratório de Carboidratos e Radioimunoensaio -LIM 18, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av Dr. Arnaldo 455, 01246-903, São Paulo, Brazil. kfbg23@hotmail.com.
authors.forename: Karla Fabiana Brasil
authors.identifier: 0000-0002-4239-5640
authors.initials: KF
authors.lastname: Gomes
authors.affiliation: Laboratório de Carboidratos e Radioimunoensaio -LIM 18, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av Dr. Arnaldo 455, 01246-903, São Paulo, Brazil.
authors.forename: Cintia
authors.initials: C
authors.lastname: Semzezem
authors.affiliation: Laboratório de Carboidratos e Radioimunoensaio -LIM 18, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av Dr. Arnaldo 455, 01246-903, São Paulo, Brazil.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Batista
authors.affiliation: Laboratório de Carboidratos e Radioimunoensaio -LIM 18, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av Dr. Arnaldo 455, 01246-903, São Paulo, Brazil.
authors.forename: Rosa Tsuneshiro
authors.initials: RT
authors.lastname: Fukui
authors.affiliation: Laboratório de Carboidratos e Radioimunoensaio -LIM 18, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av Dr. Arnaldo 455, 01246-903, São Paulo, Brazil.
authors.forename: Aritania Sousa
authors.initials: AS
authors.lastname: Santos
authors.affiliation: Laboratório de Carboidratos e Radioimunoensaio -LIM 18, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av Dr. Arnaldo 455, 01246-903, São Paulo, Brazil.
authors.forename: Márcia Regina
authors.initials: MR
authors.lastname: Correia
authors.affiliation: Departamento de Genética e Biologia Evolutiva, Instituto de Biociências da Universidade de São Paulo. Rua do Matão, 277, 05422-970, São Paulo, São Paulo, Brazil.
authors.forename: Maria Rita
authors.initials: MR
authors.lastname: Passos-Bueno
authors.affiliation: Laboratório de Carboidratos e Radioimunoensaio -LIM 18, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Av Dr. Arnaldo 455, 01246-903, São Paulo, Brazil.
authors.forename: Maria Elizabeth Rossi da
authors.identifier: 0000-0002-7470-0427
authors.initials: ME
authors.lastname: Silva
mesh_terms: D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000378:metabolism*; D001938:Brazil / Q000208:ethnology; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis* / Q000208:ethnology / Q000235:genetics / Q000276:immunology; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005968:Glutamate Decarboxylase / Q000276:immunology; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8 / Q000276:immunology; D044465:White People / Q000235:genetics; D055815:Young Adult; D000075703:Zinc Transporter 8 / Q000235:genetics* / Q000276:immunology*
chemical_list: D001323:Autoantibodies; C492522:SLC30A8 protein, human; D000075703:Zinc Transporter 8; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8; D005968:Glutamate Decarboxylase