DEFB4A Promoter Polymorphism Is Associated with Chronic Periodontitis: A Case-Control Study.

Background

Human β-defensin-2 is an antimicrobial peptide with antibiotic properties secreted by the oral cavity to protect the host against microbial attack. The inter-individual differences in defensin expression profiles due to genetic variation might be partly responsible for differences in disease susceptibility. Aims: The objective of this study was to examine whether variation in the human β-defensin-2 gene (DEFB4A) is associated with chronic periodontitis (CP). Materials and

Methods

This case-control study used Sanger sequencing to analyze two promoter polymorphisms of the DEFB4A gene with potential functional consequences using DNA samples collected from 200 unrelated individuals.

Results

The DEFB4A rs1339258595 promoter polymorphism is associated with CP risk and clinical attachment level (CAL) but the rs3762040 polymorphism is not. Carriers of the T allele (rs1339258595) were approximately three times less likely to develop periodontitis compared with noncarriers (p = 0.0004, odds ratio = 0.35). Consistent with a protective role, the carriers of T allele had a lower CAL compared with the wild-type (G) allele. Moreover, the wild-type diplotype (GGGG) had a significantly higher risk of tooth loss compared with other diplotypes (p = 0.016).

Conclusion

This study demonstrates that genetic variation in the promoter region of DEFB4A likely affects resistance to periodontal infection and might be a potential marker for CP risk and severity.