Interactions of lymphotoxin alpha (TNF-beta), angiotensin-converting enzyme (ACE), and endothelin-1 (ET-1) gene polymorphisms in adult periodontitis.
BACKGROUND
Adult periodontitis is a complex multifactorial disease whose etiology is not well defined. To investigate whether the genes encoded within the HLA class III region may confer susceptibility to periodontitis, polymorphisms in the ET-1 and TNF-beta genes were analyzed together with the I/D polymorphism of the ACE gene.


METHODS
We determined allele and genotype frequencies of the NcoI bi-allelic polymorphism of the TNF-beta gene, the I/D (insertion/deletion) polymorphism of the ACE gene, and the TaqI polymorphism of the ET-1 gene in 63 Caucasian patients with adult periodontitis and 95 orally healthy controls.


RESULTS
We found a significant difference in a 3 locus combination of genotypes between patients and controls (P<0.05). In the next analyses, no significant differences were found in allele frequencies of single genes, but we did find a significant difference in the genotype distribution between cases and controls for TNF-beta (P<0.03). Differences were also observed for 2 locus combinations of ACE and TNF-beta genotypes (P<0.03), and the ET-1 and TNF-beta (P<0.05) genes. Evidence of deviation from Hardy-Weinberg equilibrium was observed in the periodontitis group for TNF-beta, with an absence of the B1B1 homozygotes in patients.


CONCLUSIONS
This study is of an exploratory nature. Considering the number of significant results, however, at least a part of the observed associations may obviously be real and our findings suggest that interactions of the TNF-beta, ET-1, and ACE genes may be involved in susceptibility to adult periodontitis.
Hollá
L I
LI
Institute of Pathological Physiology, Medical Faculty, Masaryk University Brno, Czech Republic. holla@med.muni.cz
Fassmann
A
A
Vasků
A
A
Znojil
V
V
Vanek
J
J
Vácha
J
J
D000328:Adult; D000483:Alleles; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002874:Chromosome Mapping; D004251:DNA Transposable Elements / Q000235:genetics; D019332:Endothelin-1 / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006720:Homozygote; D006801:Humans; D008233:Lymphotoxin-alpha / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D010518:Periodontitis / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012307:Risk Factors; D017384:Sequence Deletion / Q000235:genetics; D013223:Statistics as Topic
D004251:DNA Transposable Elements; D019332:Endothelin-1; D008233:Lymphotoxin-alpha; D007703:Peptidyl-Dipeptidase A