All issues > Volume 48(6); 2005

Original Article

Korean J Pediatr. 2005;48(6):624-633. Published online June 15, 2005.

Human Leukocyte Antigen(HLA) Genotypes and Thyroid Autoimmunity in Korean Patients with Type 1 Diabetes

So Young SY Kang¹, Chung Ho CH Shin², Sei Won SW Yang², Myoung Hee MH Park³, Jeesuk JS Yu¹

¹Department of Pediatrics, Dankook University College of Medicine, Cheonan, Korea
²Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
³Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea

Correspondence Jeesuk JS Yu ,Email: dryujs@dankook.ac.kr

Abstract

Purpose
: This study analyzed the expression of HLA-DR and DQ genotypes and anti-thyroid autoantibodies[anti-thyroid peroxidase(TPO) and anti-thyroglobulin(TG) antibodies] in Korean patients with type 1 diabetes(T1DM) to investigate the susceptible HLA alleles to T1DM in Korea and the prevalence of thyroid autoantibodies and their significance for the development of thyroid disorders.
Methods
: A total of 59 Korean patients with type 1 diabetes[26 males, median age 13.7 years(range 5.7-29.9 years), diabetes duration 7.6 years(-1.7-22.5 years)] were enrolled in this study, and 200 healthy Koreans without a family history of diabetes were selected as a normal control for the comparison of HLA genotypes. Seventeen patients with anti-TPO or anti-TG were followed [median duration 3.96 years(1 day-10.7 years)] with measurement of anti-TPO, anti-TG, T3, T4 or free T4, TSH levels and physical examinations. HLA-DR and DQ genotyping were done by PCR-SSO, PCR- SSCP, PCR-RFLP and PCR-SSP methods.
Results
: HLA analysis showed higher frequencies of HLA-DRB1*0301, *090102 and DQB1*0201, *030302 alleles, DRB1*0301/*090102, *090102/*090102 and DQB1 *0201/*030302, *030302/*030302, *0201/ *0302 genotypes in T1DM patients compared to controls(Pc<0.05). Fifteen(25.4 percent) had anti- TPO antibody, 12(20.3 percent) had anti-TG, 17(28.8 percent) had either autoantibody and 10(16.9 percent) had both autoantibodies. No clinical or subclinical hypothyroidism developed during follow- up after the first detection of anti-thyroid autoantibody. There was no significant correlation between thyroid autoimmunity and gender, onset age of T1DM, and diabetes duration, respectively(P>0.05).
Conclusion
: We thought this unique HLA-DR, DQ allele distribution might be an important factor for the low incidence of T1DM in Korea. And a high prevalence of thyroid autoantibodies in these populations suggests examinations of thyroid antibodies should be performed regularly. Optimal age for the initial screening and the frequency of re-screening for associated thyroid autoimmune diseases in T1DM remains to be determined through prospective follow-up.

Keywords :Type 1 diabetes mellitus(T1DM) , HLA , Thyroid autoimmunity