Section of Periodontology, Department of Restorative Dentistry and Periodontology, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand.
J Clin Periodontol. 2012 Jun;39(6):519-25. doi: 10.1111/j.1600-051X.2012.01871.x. Epub 2012 Apr 4.
To examine the genetic diversity of Aggregatibacter actinomycetemcomitans in Thai adults.
Subgingival plaque samples from 453 subjects were analysed for A. actinomycetemcomitans serotypes, the presence of the high leukotoxin-producing JP2 clone and cytolethal distending toxin genes (cdtABC) using the polymerase chain reaction technique. In subjects who were positive for cdtABC, restriction fragment length polymorphism analysis was used to identify a single nucleotide polymorphism (SNP) in the cdtB gene at amino acid position 281. The extent and severity of periodontal disease were compared between subjects harbouring different A. actinomycetemcomitans genotypes.
Eighty six subjects (19%) were positive for A. actinomycetemcomitans. The JP2 clone was not detected. Serotype c was the most prevalent (57%), followed by serotypes a (33%) and b (7%). Among A. actinomycetemcomitans-positive subjects, 27% were positive for cdtABC. All cdtABC-positive subjects possessed the SNP in the cdtB, which is involved with increased toxin activity. The presence of A. actinomycetemcomitans, but not a specific genotype, was significantly related to increased probing depth and periodontal attachment loss.
Our results confirm the previous findings that genotype distribution of A. actinomycetemcomitans varies between ethnic groups. However, no clear relationship between a specific genotype and periodontal conditions was observed.
研究泰国成年人中伴放线放线杆菌的遗传多样性。
采用聚合酶链反应技术，对 453 名受试者的龈下菌斑样本进行分析，以确定伴放线放线杆菌血清型、高白细胞毒素产生 JP2 克隆和细胞致死扩张毒素基因（cdtABC）的存在情况。在 cdtABC 阳性的受试者中，采用限制性片段长度多态性分析（RFLP）方法，确定 cdtB 基因在氨基酸位置 281 处的单核苷酸多态性（SNP）。比较携带不同伴放线放线杆菌基因型的受试者牙周病的严重程度和严重程度。
86 名受试者（19%）为伴放线放线杆菌阳性。未检测到 JP2 克隆。血清型 c 最为常见（57%），其次是血清型 a（33%）和 b（7%）。在伴放线放线杆菌阳性的受试者中，27%的人 cdtABC 阳性。所有 cdtABC 阳性的受试者均存在 cdtB 中的 SNP，这与毒素活性增加有关。伴放线放线杆菌的存在，而不是特定的基因型，与增加的探测深度和牙周附着丧失显著相关。
我们的结果证实了先前的研究结果，即伴放线放线杆菌的基因型分布在不同种族之间存在差异。然而，没有观察到特定基因型与牙周状况之间存在明确的关系。
