ESPE Abstracts

Introducion: Autoimmune thyroid diseases (AITDs): Hashimoto's thyroiditis (HT) and Graves’ disease (GD) are common chronic autoimmune endocrine disorders in children. The mechanisms leading to the development of these diseases remain unknown, however scientific reports indicate that in addition to environmental factors, genetic background plays an important role. In our previous studies, we showed that some polymorphisms of the genes for IL2RA, FAIM2, IFIH1, PADI4 or CTLA-4 appeared more frequently in children and adolescents with autoimmune diseases like type 1 diabetes (T1D) and AITDs, which may be related to the occurrence and course of the disease. According to the literature, a number of other factors involved in immune mechanisms are known to potentially influence the development of autoimmune disease. The aim of this study was to assess the prevalence of selected single nucleotide polymorphisms (SNPs) of Il7R, CD226, CAPSL and CLEC16A genes in children and adolescents with autoimmune thyroid diseases.

Materials and Methods: We performed this study in the group of 56 HT patients (mean age, 15.2 ± 2.2 years) 124 GD patients (mean age, 16.5 ± 2 years) and a 156 healthy children as a control. We analyzed SNPs at the loci rs3194051, rs6897932 for IL7R gene, rs763361 for CD226 gene, rs1010601 for CAPSL gene and rs725613 for CLEC16A gene.

Results: We observed significant differences in allels IL7R (rs6897932) between HT boys and control group (C > T, P=0.028) and between all GD patients and healthy children (C > T, P= 0.035) as well as GD girls and controls (C > T, P=0.018). Moreover C/C genotype at rs6897932 of IL7R gene was statisticaly significant more frequent in all GD patients. In addition, the study revealed C/C genotype at the CAPSL locus (rs1010601) in HT boys to be statisticaly significant more frequent in comparison to control group. We observed no significant differences between AITD patients and a control group in other analysed SNPs (rs3194051 for IL7R, rs763361 for CD226 and rs725613 for CLEC16A).

Conclusions: The presence of T allel in the IL7R (rs6897932) locus appears to have a potential protective effect against HT in boys, as well as GD in all children. Similarly, the presence of allel T in the CAPSL locus (rs1010601) seems to reduce the risk of HT development in all pediatric patients. Our observations need to be confirmed in studies on a larger group of pediatric patients.