Prevalence of fimA genotypes of Porphyromonas gingivalis and periodontal health status in Chinese adults.
OBJECTIVE
Porphyromonas gingivalis fimbriae play a key role in colonization of the oral cavity. The fimA gene, which encodes fimbrillin (FimA), can be classified into six types (I-V and Ib) according to nucleotide sequence. In the present study, we investigated the relationship between the prevalence of P. gingivalis-specific fimA genotypes and periodontal health status in Chinese adults.


METHODS
One-hundred and fifteen patients with chronic periodontitis and 136 periodontally healthy adults were selected. P. gingivalis detection, determination of fimA genotypes, and the co-existence of Actinobacillus actinomycetemcomitans and Tannerella forsythia with various fimA types, were assessed by the polymerase chain reaction. Odds ratios and 95% confidence intervals were calculated for associating the fimA-specific genes with periodontitis.


RESULTS
P. gingivalis was detected in 22.1% of healthy subjects and in 81.7% of the patients. A single fimA genotype was detected in most samples. In healthy adults, the most prevalent fimA genotype was type I (66.7%). However, type II was detected most frequently (43.6%) in the patient group, followed by type IV (30.9%). The frequency of co-existing A. actinomycetemcomitans and T. forsythia was highest in type II fimA-positive sites. Statistical analysis revealed that periodontitis was associated with occurrences of type I (odds ratio 0.97), Ib (odds ratio 13.26), II (odds ratio 36.62), III (odds ratio 4.57), IV (odds ratio 22.86) and V (odds ratio 1.19).


CONCLUSIONS
P. gingivalis type II followed by type IV were considered as disease-associated strains that account for the pathogenesis of chronic periodontitis in Chinese adults.
Zhao
L
L
Key Laboratory of Oral Biomedical Engineering, Ministry of Education, Chengdu, Sichuan, China.
Wu
Y-F
YF
Meng
S
S
Yang
H
H
OuYang
Y-L
YL
Zhou
X-D
XD
D000328:Adult; D000368:Aged; D016976:Aggregatibacter actinomycetemcomitans / Q000235:genetics; D001439:Bacteroides / Q000235:genetics; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002681:China; D002908:Chronic Disease; D005260:Female; D036781:Fimbriae Proteins / Q000145:classification / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D016017:Odds Ratio; D010518:Periodontitis / Q000235:genetics / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D016966:Porphyromonas gingivalis / Q000235:genetics* / Q000472:pathogenicity
C063055:fimbrillin; D036781:Fimbriae Proteins