This study aimed to elucidate the associations between interleukin-4 (IL-4) single nucleotide polymorphisms (SNPs), 590C/T and 589C/T, serum IL-4 levels, and atopic dermatitis (AD) in children.
Methods: A total of 82 children with AD were randomly selected as the case group and divided into mild group (15 cases), moderate group (46 cases), and severe group (21 cases). Additionally, 100 healthy children were selected as the control group. Genotype frequencies of IL-4 SNPs were detected by PCR-RFLP. Serum IL-4 levels were measured by ELISA.
Results: Significant differences were shown in genotype distributions and allele frequencies of 589C/T and allele frequencies of 590C/T (all P < 0.05). Serum IL-4 levels in the mild, moderate, and severe groups were significantly higher than those in the control group; significant differences were found among these three groups with increased severity of AD. Serum IL-4 levels of heterozygote and mutant homozygote carriers in the mild, moderate, and severe groups were higher than wild homozygote carriers in those three groups and the control group (all P < 0.05).
Conclusion: 590T and 589T alleles of IL-4 gene may be associated with high levels of serum IL-4, which may increase the risk of AD in children.