Association of interleukin (IL)-4 variable number of tandem repeats (VNTRs) and IL-4-590 promoter polymorphisms with susceptibility to pediatric autoimmune hepatitis type 1.

Objective: Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease mediated by an autoimmune reaction to hepatocytes, the present study aimed to assess the possible associations between interleukin-4 (IL-4) variable number of tandem repeats (VNTRs) and IL-4-590 promoter polymorphisms and susceptibility to autoimmune hepatitis type 1 in children.

Subjects And Methods: The study was performed on 101 children diagnosed with AIH and 104 apparently healthy, age and sex-matched control children, diagnosis of AIH was based on the simplified score for the diagnosis of AIH. Genotyping for the IL-4 VNTR and IL-4-590 were performed using PCR-RFLP.

Results: The distribution of genotype frequencies of IL-4 gene intron 3 VNTR polymorphism were not significantly different between AIH patients and controls for 3R/2R and 2R/2R genotypes, while the 2R allele distribution was significantly higher among AIH patients than the control group. The frequency of IL-4-590 single nucleotide polymorphism (SNP) CT and TT genotypes was statistically higher among AIH patients than controls.

Conclusion: This study revealed the presence of an association between IL-4 -590 TT genotype and T alleles with increased AIH risk in pediatric patients, also assess its severity as they were detected with Child Plugh scores B and C.