IL4 gene polymorphisms and their relation to periodontal disease in a Macedonian population

Genetic polymorphisms in the interleukin-4 (IL4) gene have been reported to influence the host response to microbial challenge by altering levels of cytokine expression. We analyzed nucleotide polymorphisms in the promoter region of the IL4 gene and its relation with periodontal disease in a Macedonian population. The study population consisted of 92 unrelated subjects with chronic periodontitis and 286 healthy controls. DNA was isolated and IL4 genotyping performed by polymerase chain reaction-single-strand polymorphism (Heidelberg kit) for the alleles and genotypes of IL4 -1098, IL4 -590, and IL4 -33. Frequencies of IL4 haplotypes and the haplotype zygotes were also examined. Comparisons between groups were tested using the Pearson's p value. After Bonferroni adjustment, significant associations were detected between subjects with periodontitis and the following: (1) cytokine alleles IL4 -1098 and IL4 -33; (2) cytokine genotypes IL4 -1098/G:T; IL4 -1098/T:T, and IL4 -33/T:T, (3) cytokine haplotypes IL4/GCC, IL4/TCC, and IL4/TTC; and (4) cytokine haplotype zygotes IL4/TTC: TCC, IL4/TCT:TTT, and IL4/GCC:TTC. Cytokine polymorphism on the IL4 gene appears to be associated with susceptibility to chronic periodontitis in Macedonians.