The Study of kgp Genetic Difference of Porphyromonas Gingivalis in Subgingival Plaque

Objective:To analyse the genetic polymorphism of Lys-gingipain (kgp),a virulent factor of porphyromonas gingivalis (P. gingivalis) and discuss the role of the different genotypes in the genesis and progress of chronic periodontitis. Methods:A total of 104 subgingival plaque samples were included in this study. According to the sequence of kgp-cd,P.gingivalis was typed into four genotypes by restriction fragment length polymorphism(RFLP). Results:The detection rate of typeⅡ was the highest(56.25%)in lesion site,while that of type Ⅰ(51.72%) was the highest in non-lesion site. In healthy site,only type Ⅰ(25%) and Ⅲ(75%) were detected. Conclusion:The polymorphism of kgp-cd gene may influence the virulence of P.gingivalis. P.gingivalis type Ⅱ may be well related to periodontitis,while type Ⅰ may be a indigenous flora.