ABSTRACT
BACKGROUND: Cytokine gene polymorphisms are known to influence the susceptibility and disease course of many chronic disorders. Recently, interleukin (IL)-4 gene polymorphisms were associated with aggressive periodontitis. The aim of this study was to test differences in the distribution of the IL-4 alleles, genotypes, and haplotypes between patients with chronic periodontitis (CP) and healthy controls in a Czech population. METHODS: The association study was conducted using an age- and smoking status-matched case-control design in patients with CP (n = 194) and healthy controls (n = 158) using the polymerase chain reaction-restriction fragment length polymorphism methods for the -590C/T, -33C/T, and intron 3 variable number tandem repeat (VNTR) variants of the IL-4 gene. RESULTS: No significant differences between patients and controls were found in allele and genotype frequencies of all three polymorphisms. Nevertheless, complex analysis revealed significant differences in haplotype frequencies between the groups (P = 0.005). The haplotype T(-590)/T(-33)/allele 2 VNTR (70 base pairs)(2) of the IL-4 gene was significantly more frequent in patients with CP than in controls (17.0% versus 11.0%; odds ratio = 1.85; 95% confidence interval: 1.19 to 2.87). CONCLUSION: The three polymorphisms in the IL-4 gene act in a cooperative fashion and suggest that the high-production IL-4 haplotype was associated with an increased risk for CP in the Czech population.
Subject(s)
Chronic Periodontitis/immunology , Haplotypes/genetics , Interleukin-4/genetics , 5' Flanking Region/genetics , Adult , Alleles , Base Pairing/genetics , Case-Control Studies , Chronic Periodontitis/genetics , Cytosine , Czech Republic , Exons/genetics , Female , Gene Frequency , Genetic Predisposition to Disease/genetics , Genotype , Humans , Introns/genetics , Male , Middle Aged , Polymerase Chain Reaction , Polymorphism, Genetic/genetics , Polymorphism, Restriction Fragment Length , Polymorphism, Single Nucleotide/genetics , Tandem Repeat Sequences/genetics , ThymineABSTRACT
OBJECTIVES: Transforming growth factor-beta (TGF-beta) represents a family of polypeptide growth factors, involved in inflammation and regulation of immune responses. The purpose of this study was to determine whether polymorphisms in the TGF-beta 1 gene may confer susceptibility to adult periodontitis. MATERIAL AND METHODS: We studied 90 patients with adult periodontitis together with 108 unrelated subjects. 3 polymorphisms located in the 5'region at positions -988 (C/A), -800 (G/A) and -509 (C/T) and 2 polymorphisms located at codons 10 (L10P) and 25 (R25P) of exon 1 were investigated by PCR methods. RESULTS: There was no statistically-significant difference in genotype or allele frequency distributions between patients and reference group for the -800G/A, -509C/T, L10P and R25P polymorphisms (p>0.05 in all cases). The -988 A polymorphism was present neither in our patients nor in unrelated subjects. Upon stratification for smoking status no significant differences were found in the TGF-beta 1 genotype or allele frequencies either between adult periodontitis smokers compared to control smokers, or between periodontitis non-smokers and control non-smokers. CONCLUSION: These data indicate that the mentioned polymorphisms of the TGF-beta 1 gene do not influence susceptibility to adult periodontitis. There was no association between any polymorphisms in the TGF-beta 1 gene, severity of periodontitis and the smoking status in our study.
