OBJECTIVE: Recent studies have showed that genetic factors involved in the host responses might determine the severity of periodontitis. hCAP-18/LL-37 is a part of the innate immune response in the oral cavity. The aim of the present study was to investigate the mutation of CAMP gene encoding hCAP-18/LL-37 in the patients with different periodontal diseases.
DESIGN: Seventy-eight chronic periodontitis, 72 generalized aggressive periodontitis, and 149 controls were analysed for mutation of CAMP gene using direct DNA sequencing method. Frequencies of p.S34N mutation were compared by Pearson chi-square test. Logistic regression analysis was used to analyse the association between periodontitis and p.S34N mutation adjusting for bleeding on probing, age and gender.
RESULTS: Twenty-five subjects had a novel missense mutation of CAMP gene. Single base substitution (c.101G>A) in exon 1 led to p.S34N mutation. All amino acid substitutions were heterozygous mutation. The patients with generalized aggressive periodontitis had significantly higher p.S34N mutation prevalence compared to the others, whilst there was no significant difference in prevalence of p.S34N mutation between the patients with chronic periodontitis and the control subjects. Logistic regression analysis adjusted for BOP, age and gender revealed that the patients with generalized aggressive periodontitis were 5.32 times more likely to have p.S34N mutation compared to the controls (OR=5.32, 95% CI: 1.3-22.1).
CONCLUSION: We report a novel missense mutation of CAMP gene. p.S34N mutation in CAMP gene seems to be contributing factor for generalized aggressive periodontitis, but not for chronic periodontitis.