title: Influence of cytotoxic T lymphocyte antigen-4 (CTLA-4) gene polymorphisms in periodontitis.
abstract: OBJECTIVE
  Persistent host inflammatory immune response against the pathogens results in the destruction of periodontal tissues. Cytotoxic T lymphocyte antigen 4 (CTLA-4) is a particularly important molecule in down-regulating T-cell expansion and cytokine production. This study aimed to assess three functional SNPs within CTLA-4 gene, -1722 T/C, -318 C/T, and +49 A/G in patients with aggressive or chronic periodontitis.
  
  
  METHODS
  A total of 197 patients with periodontitis (71 aggressive and 126 chronic periodontitis) and 218 healthy controls were recruited. All samples were genotyped for CTLA-4 gene polymorphisms by polymerase chain reaction-amplification refractory mutation system (PCR-ARMS).
  
  
  RESULTS
  The allelic and genotype frequencies of only +49 A/G SNP were more prominence in patients with chronic periodontitis (CP) than that controls (0.0005 and 0.001, respectively). Multivariate logistic regression analysis was demonstrated that homozygosity in +49 G/G had profoundly increased susceptibility for CP, OR=3.7 (95% CI; 1.6-8.5, P=0.001). In addition, comparison of CTLA-4 SNPs between patients with CP and aggressive periodontitis (AgP) revealed that heterozygosity in -1722 T/C polymorphism of CTLA-4 gene had a significantly higher risk for CP compared with AgP with a calculated odds ratio of 2.18 (95% CI; 1.17-4.06, P=0.01).
  
  
  CONCLUSIONS
  These results suggest that CTLA-4 gene variants might be associated to susceptibility to specific form of periodontitis and participate in the CP development.
authors.affiliation: Department of Periodontology, Faculty of Dentistry, Shaheed Beheshti University of Medical Sciences/National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
authors.forename: B
authors.initials: B
authors.lastname: Houshmand
authors.forename: A
authors.initials: A
authors.lastname: Rafiei
authors.forename: M
authors.initials: M
authors.lastname: Hajilooi
mesh_terms: D000225:Adenine; D000293:Adolescent; D000328:Adult; D000368:Aged; D010520:Aggressive Periodontitis / Q000235:genetics / Q000276:immunology*; D000483:Alleles; D060908:CTLA-4 Antigen / Q000235:genetics*; D055113:Chronic Periodontitis / Q000235:genetics / Q000276:immunology*; D003596:Cytosine; D003774:Dental Plaque Index; D005091:Exons / Q000235:genetics; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D005884:Gingival Hemorrhage / Q000145:classification; D006147:Guanine; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D017622:Periodontal Attachment Loss / Q000145:classification; D010514:Periodontal Pocket / Q000145:classification; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012307:Risk Factors; D013941:Thymine; D055815:Young Adult
chemical_list: D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; D006147:Guanine; D003596:Cytosine; D000225:Adenine; D013941:Thymine