Interleukin-4 polymorphisms in early onset periodontitis

Background, aims: Periodontitis is the result of a complex interplay between oral bacteria and the host response, often modulated by behavioral factors. Early-onset periodontitis (EOP) is defined by the age of onset, the distribution of lesions and specific microbial pathogens. Method: Studies in twins suggested a genetic contribution to the pathogenesis of periodontitis. EOP heritable factors may be related to immune mechanisms which could enhance the pathogenic potential of plaque bacteria in susceptible individuals. Among others, Interleukin 4 (IL-4) is a potent cytokine in the immune response and is a potent down regulator of macrophage function. In the present study, we report a specific genotype of the IL-4 gene, which was detected by specific primers and PCR analysis. Results: In the EOP-group 27.8% were IL-4 promotor- and intron polymorphism positive (PP+ and IP+). None of the age-matched healthy controls or patients with adult periodontitis (n=25) carried the markers. Moreover, serum IL-4 levels of PPS and IP+ patients were below the detection limit and significantly different (p < 0.01) from the IL-4 concentrations of healthy controls and PP- and IP- patients.