The IL18 gene and Hashimoto thyroiditis in children

Area of Science:

• Immunogenetics
• Endocrinology
• Pediatric Autoimmunity

Background:

• Interleukin 18 (IL18) promotes interferon-gamma production in Th1 cells, which are prevalent in the thyroid tissue of individuals with Hashimoto thyroiditis (HT).
• Understanding the genetic underpinnings of HT is crucial for identifying individuals at risk and developing targeted interventions.

Purpose of the Study:

• To investigate the potential association between specific genetic variations in the Interleukin 18 (IL18) gene and the risk of developing Hashimoto thyroiditis (HT) in a pediatric population.

Main Methods:

• Genotyping of single nucleotide polymorphisms (SNPs) rs187238 and rs1946518 within the promoter region of the IL18 gene.
• Comparative analysis of genotype, allele, carrier, and haplotype frequencies between 116 children with HT and 1272 healthy controls.
• Statistical evaluation using Pc values, with significance set at <0.05, and calculation of odds ratios (OR) and 95% confidence intervals (CI).

Main Results:

• The C/G genotype and C allele of rs187238 were significantly more frequent in children with HT, indicating an increased risk (OR=1.96, Pc=0.0021 for genotype; OR=1.73, Pc=0.0035 for allele).
• The G/G genotype of rs187238 was significantly less frequent in HT patients (OR=0.51, Pc=0.0034).
• The CT haplotype of the IL18 gene promoter was also significantly associated with an increased risk of HT (OR=1.76, Pc=0.0049).
• No significant association was found between HT and the rs1946518 polymorphism.

Conclusions:

• The IL18 gene, particularly the rs187238 polymorphism, is significantly associated with Hashimoto thyroiditis in children.
• The rs187238C allele and the CT haplotype represent genetic risk factors for developing HT in pediatric populations.