Investigation of functional gene polymorphisms interleukin-1β, interleukin-6, interleukin-10 and tumor necrosis factor in individuals with oral lichen planus

Oral lichen planus (OLP) is a chronic inflammatory oral mucosal disease. There are some studies in the literature demonstrating association between cytokines genes polymorphisms and susceptibility to develop some immune-mediate conditions. The purpose of this study was to investigate cytokine gene polymorphisms in a sample of Brazilian patients with OLP. Fifty-three patients with OLP (mean age = 43.1 years; range 20-68 years) and 53 healthy volunteers (mean age = 42.9 years; range 21-67) were genotyped for IL-1beta +3954 (C/T), IL-6-174 (G/C), IL-10-1082 (G/A) and TNFA-308 (G/A) gene polymorphisms. Statistical analysis was based on the use of logistic regression (P-values below 0.05 were considered as significant). IL-6 and TNFA homozygous genotypes were significantly more often detected in OLP patients. These genotypes were associated with an increased risk of OLP development (OR 6.89 and 13.04, respectively). IL-1beta and IL-10 gene polymorphisms were not related to OLP development. Our findings clearly demonstrate an association between inheritance of IL-6 and TNFA gene polymorphisms and OLP occurrence, thus giving additional support for genetic basis of this disease.     

Analysis of the association of IL1B (C+3954T) and IL1RN (intron 2) polymorphisms with dental implant loss in a Brazilian population

Background: Although dental implants have a high success rate, failures occur, in spite of adequate clinical conditions. Together with the observation that multiple implant losses occur in certain groups of individuals (clusterization phenomenon), this suggests that host response may influence implant failure. Little is known about the influence of genetic susceptibility on implant loss. Interleukin (IL)-1β and IL-1ra are believed to play a key role in the immune-inflammatory response, and polymorphisms IL1B (C+3954T) and IL1RN (intron 2) are shown to alter the coding proteins expression.
Objectives: The aim of this study was to investigate the association between dental implant loss and polymorphisms IL1B (+3954) and IL1RN (intron 2).
Material and methods: The study population ( n =266) was divided into Test group (T) – 90 subjects with implant loss, and Control group (C) – 176 subjects without any implant failure. Genotyping was performed by PCR-RFLP.
Results: The number of present teeth was observed to influence implant loss. No differences in genotype and allele frequencies between C and T were found for IL1B (+3954) and IL1RN (intron 2) polymorphisms. However, the analysis of the whole study population (control and test groups) showed that genotype 2/2 was significantly more frequent in individuals with multiple implant losses ( n =35) than in individuals that lost up to a single implant ( n =231) (OR: 3.07, IC: 1.13–8.34, P =0.027).
Conclusion: It was observed that number of teeth and edentulism were associated with implant loss. Genotype 2/2 of IL1RN polymorphism was significantly more frequent in patients who presented multiple losses, which suggests that the clusterization phenomenon has a genetic basis.     

Functional variants of IL4 and IL6 genes and risk of tobacco-related oral carcinoma in high-risk Asian Indians

Oral Diseases (2011) 17 , 720–726 Background: Tobacco‐related oral squamous cell carcinoma (OSCC) is one of the most common cancers involving Indian males. We assessed the association of IL4 promoter –589 T>C, –33 T>C, and IL6–174 G>C functional genetic polymorphisms with tobacco‐related OSCC in Asian Indians. Patients and Methods: The IL4 and IL6 promoter polymorphisms were assessed in 140 patients with OSCC and 120 normal subjects by PCR–RFLP technique, and significance of the data was determined using chi‐square test. Results: The frequency of TC, CC genotype, and C allele at IL4 promoter sites –589 and –33 were higher in patients when compared with controls. Consequently, TC/CC genotypes and C allele at both sites appeared as susceptible. However, IL6–174 G>C single‐nucleotide polymorphisms (SNP) appeared to be protective in patients with OSCC. Of eight haplotypes, five were associated with two‐ to seven‐fold increased risk of tobacco‐related OSCC. These SNPs further showed heterogeneity among different ethnic population, but their distribution in Asian Indians stand closer to other Asian populations. Conclusions: In this study, IL4–589 CC, –33 CC genotype, and *C allele at both sites appeared to be susceptible, while IL6–174 CC genotype and *C allele appeared to be protective in patients with OSCC; hence, these SNPs may be a potential prognostic markers for tobacco‐related OSCC in Asian Indians.     

Coronary heart disease and chronic periodontitis: is polymorphism of interleukin‐6 gene the common risk factor in a Chinese population?

Oral Diseases (2011) 17 , 270–276 Objectives: Coronary heart disease (CHD) and chronic periodontitis (CP) both are multifactorial chronic diseases and related to inflammation. Interleukin‐6 (IL‐6) plays an important role in the pathogenesis of inflammatory diseases. The purpose of the study was to investigate the association among IL‐6 gene polymorphisms, CP and CHD susceptibility in a Chinese population. Material and methods: The investigation was conducted as a case‐control study involving 505 individuals: 113 patients with CHD and CP, 84 patients with CHD, 178 patients with CP and 130 control individuals. The polymorphisms of IL‐6 gene were analyzed by polymerase chain reaction‐restriction fragment length polymorphism. Relationships between the distributions of the genotypes and risk factors were also assessed. Results: Mutations at the loci ‐174 G/C, ‐597 G/A of IL‐6 were rare in a Chinese population. No significant difference for IL‐6‐572C/G polymorphism was detected among moderate CP group, severe CP group and control (P = 0.312 and 0.481), significant differences were found between CHD groups and non‐CHD groups (P ≤ 0.001). After adjustment for CHD risk factors, the G allele resulted in an increased risk (OR = 1.676‐1.856), the GG/CG genotype was nearly two times higher risk compared to CC genotype (OR = 2.010‐2.136). Conclusions: IL‐6‐572C/G polymorphism did not correlate with CP susceptibility, but might be a potential risk factor for CHD in a Chinese population.     

IL6 −174 Genotype Associated with Aggregatibacter actinomycetemcomitans in Indians

Oral Diseases (2011) 17 , 232–237 Aim: Genetic factors have recently been associated with presence of Aggregatibacter actinomycetemcomitans subgingivally in populations living in industrialized countries. The aim of this study was to analyse associations between Interleukin‐6 (IL6) single nucleotide polymorphisms and presence and levels of A. actinomycetemcomitans and other subgingival microbes in a rural Indian population. Subjects and Methods: A total of 251 individuals from a rural village in India with a periodontal phenotype ranging from healthy to severe periodontitis were included. Checkerboard DNA‐DNA analysis was performed to detect 40 periodontal taxa in subgingival plaque samples. Genomic DNA was extracted to genotype five polymorphisms in the IL6 promoter region. Results: The IL6 ?174 GG genotype was associated with high (above median) counts of A. actinomycetemcomitans (both in all subjects and in periodontally healthy only) and with presence and counts of Capnocytophaga sputigena. Differences in detection of several other bacteria were noted between periodontitis and healthy subjects. Conclusions: These findings support the influence of genetic factors on the subgingival microbiota.     

IL-6基因多态性与汉族人群慢性牙周炎敏感性关系的研究

目的　探讨IL 6基因多态性与汉族人群慢性牙周炎敏感性的关系。方法　收集了汉族轻、中、重度慢性牙周炎共 16 6例和 80例健康对照的颊粘膜拭子 ,以Chelex 10 0法提取DNA ,用PCR -RFLP法检测IL 6 174的多态性 ,比较患者和对照组中基因型分布和等位基因频率的差异。结果　轻、中、重度慢性牙周炎患者中IL 6 174位点的基因型分布在患者组和对照组间无明显差别 ,汉族中IL 6 174位点等位基因C的频率极少 ,明显低于高加索人。结论　IL 6 174位点的基因多态性与汉族人群慢性牙周炎敏感性无关     

白细胞介素-6基因-174G/C、-572C/G多态性与冠心病和慢性牙周炎的相关性的研究

目的研究白细胞介素-6基因-174G/C、-572C/G多态性与冠心病和慢性牙周炎易感性的关系。方法采用病例对照实验设计,选择129例冠心病伴中重度慢性牙周炎患者、47例冠心病患者、131例中重度慢性牙周炎患者和121例健康者,应用聚合酶链反应-限制性内切酶片段长度多态性基因分析方法,比较IL-6基因-174、-572位点基因型和等位基因频率在各组间分布特点。结果IL-6基因-174位点C等位基因在各组检出率极低为0%～0.8%。GG、GC两种基因型和G、C等位基因频率在组间分布差异无统计学意义（P〉0.05）。IL-6基因-572位点CC、GC、GG三种基因型和C、G等位基因频率在健康组和牙周炎组间分布差异无统计学意义（P〉0.05）,在冠心病组和非冠心病组间分布差异有统计学意义（P〈0.05）,G等位基因在冠心病组的检出率明显高于非冠心病组,差异有统计学意义（P〈0.01）。结论IL-6基因-174位点在中国汉族人群中变异率低。-572位点的多态性与慢性牙周炎的易感性无关,与冠心病有关,-572位点G等位基因可能是冠心病的易感标志。     

Analysis of the interleukin-6 gene promoter polymorphisms in Czech patients with chronic periodontitis

BACKGROUND: Chronic periodontitis is an inflammatory disease, which is a major cause of tooth loss. The proinflammatory cytokines interleukin-1 (IL-1) and interleukin-6 (IL-6) are key regulators of the host response to microbial infection and major modulators of extracellular matrix catabolism and bone resorption. The purpose of this study was to investigate the associations of chronic periodontitis with IL-6 gene polymorphisms (at positions -597 [G/A], -572 [G/C], and -174 [G/C]). METHODS: We analyzed allele, genotype, and haplotype distributions of the IL-6 promoter variants in a case-control study involving 148 patients with chronic periodontitis and 107 unrelated controls. RESULTS: Our results showed significant differences in the distributions of alleles and genotypes of the IL-6 (-572 G/C) polymorphism between patients and the control population (chi2 = 10.393, P= 0.001, P(corr) < 0.01). The difference was due to the underrepresentation of the -572 G/C heterozygotes in patients (6.1%) compared to controls (19.6%). Although no variant "CC" homozygotes were detected in our cases and controls, heterozygosity protected against chronic periodontitis, representing a 73% reduction of risk (odds ratio [OR] = 0.27, 95% confidence interval: 0.12-0.61) compared to wild-type homozygotes. However, there were no significant differences in genotype or allele frequencies between both groups for IL-6 -597 G/A and -174 G/C polymorphisms. CONCLUSION: This study is the first, to our knowledge, suggesting that the -572 G/C polymorphism of the IL-6 gene may be one of the protective factors associated with lower susceptibility to chronic periodontitis.     

The IL1A (-889) gene polymorphism is associated with chronic periodontal disease in a sample of Brazilian individuals

BACKGROUND AND OBJECTIVE: It has been proposed that genotypes reflective of polymorphisms in cytokine genes can predispose individuals to disease by enhancing inflammatory processes. The C/T polymorphism at position -889 of the IL1A gene influences interleukin-1alpha expression, with the T allele inducing higher expression. The aim of this study was to evaluate the association of the IL1A (-889) gene polymorphism in Brazilian individuals with different clinical forms of periodontitis and severity of disease. MATERIAL AND METHODS: DNA was obtained from oral swabs of 163 Brazilian individuals and was amplified using the polymerase chain reaction (PCR). Products were submitted to digestion and were analyzed by electrophoresis to distinguish the C and T alleles. RESULTS: A significant difference in the genotype distribution was observed when comparing the chronic periodontitis group with the control group, evaluating only nonsmokers (chi-squared analysis = 9.91; p = 0.007), as well as when smokers were included (chi-squared analysis = 6.36; p = 0.04). Moreover, we observed a higher incidence of the T allele in the chronic periodontitis group (37.8%) when compared with the control group (18.4%) in nonsmokers (p = 0.006, odds ratio = 2.69, confidence interval = 1.27-5.68) and also when smokers were included (p = 0.03, odds ratio = 1.87, confidence interval = 0.98-3.56). No statistical difference was observed when the aggressive periodontitis group was compared with the control group. With regard to severity of disease, no statistical difference was observed. CONCLUSION: These data show an association of the IL1A (-889) polymorphism with chronic periodontitis in Brazilian individuals.     

Proinflammatory and anti-inflammatory cytokine gene polymorphisms in hypersensitivity pneumonitis

Hypersensitivity pneumonitis (HP) is an immunologically-mediated lung disease caused by repeated inhalation of dispersed antigen. Various cytokines have been reported to be involved in the immunopathogenesis of HP Recently, some reports suggested an association between the genetic control of cytokine production and disease susceptibility. To evaluate whether cytokine gene polymorphisms are associated with HP, we performed a case-control association study involving 61 patients with HP, consisting of summer-type HP (SHP) and bird fancier's lung (BFL, also named bird fancier's disease), as well as 101 healthy controls. Polymorphisms of the genes for tumor necrosis factor (TNF)-alpha (-308G/A, -857C/T, -863C/A, -1031T/C), interleukin (IL)-10 (-592C/A, -819C/T, -1082G/A), transforming growth factor (TGF)-beta1 (-509C/T, +869T/C), and IL-6 (-634C/G) were examined by restriction fragment length polymorphism analysis. There were no significant differences in allele frequency and genotype distribution among control, SHP, and BFL group. When HP group was divided into acute or chronic, no significant differences were detected between any groups. LPS-stimulated IL-6 secretion by whole blood cells was similar between subjects with GG genotype and non-GG genotype in IL-6 -634C/G polymorphism. In conclusion, the association between HP susceptibility and cytokine polymorphisms studied was not demonstrated.     

Association of IL1 gene polymorphisms with chronic periodontitis in Brazilians

Chronic periodontal disease (PD) is an infectious immune-inflammatory illness. Polymorphisms in IL1 genes play a role in inflammatory diseases through the modulation of cytokine levels.

Objective

This study aimed to investigate the association between polymorphisms in the IL1 gene cluster and chronic periodontitis in a Brazilian population.

Design

A sample of 113 subjects over 25 years (mean age 41.2) were grouped into: 44 healthy individuals, 31 subjects with moderate and 38 with severe periodontitis. DNA was obtained through a mouthwash and oral mucosa scraping. PCR-RFLP was used to identify the following polymorphisms: IL1A C − 889T (rs1800587), IL1B C − 511T (rs16944), IL1B C + 3954T (rs11436340), IL1RN intron 2 (rs2234663). Differences in the allele/genotype/haplotype frequencies were assessed by Chi-square test (p < 0.05). The risk associated with alleles, genotypes and haplotypes was calculated as odds ratio (OR) with 95% confidence intervals (CI).

Results

Neither IL1A (C − 889T) nor IL1B (C + 3954T) polymorphisms was associated with chronic PD. Allele T for IL1B (C − 511T) only associated with PD in the group of blacks and mulattos. Moreover, genotype 2/2 for IL1RN (intron 2) was associated with severe PD.

Conclusions

Genotype 2/2 of IL1RN for the whole Brazilian population and allele T of IL1B (C − 511T) in a subgroup of Afro-Americans and mulattos were suggested as putative risk indicators for chronic periodontitis.     

Investigation of functional gene polymorphisms: IL-1B, IL-6 and TNFA in benign migratory glossitis in Brazilian individuals

BACKGROUND: Benign migratory glossitis (BMG) is a very common immunological oral disease of unknown aetiology. METHODS AND SUBJECTS: Fifty-three consecutive subjects affected by BMG and 53 age- and sex-matched control subjects were genotyped for IL-1B, IL-6 and TNFA polymorphisms. Binary logistic regression models were fitted and values of P < 0.05 were considered significant. RESULTS: A significant difference in the distribution of IL-1B genotypes was observed in the group with BMG in univariate analyses (P = 0.01). The multivariate analyses showed that the CT genotype of the IL1-B gene was significantly associated with a high risk to develop BMG (P = 0.02, OR 2.76). The combined presence of IL-1beta high and intermediate producers genotypes was also associated with BMG in multivariate analyses (P = 0.01, OR 3.05). IL-6 and TNFA polymorphisms were not associated with BMG in the univariate and multivariate analyses. CONCLUSION: Our findings demonstrate that the polymorphism +3954 IL-1B is associated with an increased risk of BMG development and suggest a genetic basis for disease development.     

Interleukin-6 gene polymorphism in renal transplant patients with and without gingival overgrowth

OBJECTIVE: To determine whether there is an association between genotypes of interleukin-6 (IL-6) and gingival overgrowth in kidney transplant patients. METHODS: Sixty-three unrelated kidney transplant patients suffering from gingival overgrowth as well 125 control transplant patients without overgrowth were enrolled into the study. Gingival overgrowth was assessed by two independent periodontal specialists at 6 months after transplantation. During the post-transplant period, all patients were given medication, which included cyclosporin A, diltiazem or verapamil, prednisone, and azathioprine. IL-6 polymorphism was determined using the polymerase chain reaction-restriction fragment length polymorphism assay. RESULTS: In kidney transplant patients suffering from gingival overgrowth mean score of gingival overgrowth was 1.41+/-0.64, whereas in control subjects it was 0.0. Patients with gingival overgrowth induced by immunosuppressive medication were characterized by genotypes similar to the controls distribution of IL-6. There were no significant differences of analyzed genotypes' distribution, i.e. -174G/G, -174G/C and -174C/C between patients with gingival overgrowth 33.3%, 39.7%, 27.0% and without gingival overgrowth 30.4%, 49.6% and 20.0%, respectively. The risk of gingival overgrowth was the highest among patients carrying -174C/C genotype (OR 1.48), but did not differ markedly from the other genotypes, i.e. -174G/G (OR 1.15) and -74G/C (OR 0.67). Similar to genotypes, the distribution of alleles was similar in patients with gingival overgrowth and healthy gingiva. The -174G allele was found in 53.2% and 46.8% of subjects whereas -174C allele was revealed in 46.8% and 44.8% of patients with and without gingival overgrowth, respectively. The evaluated risk of gingival overgrowth in patients with -174G allele was 1.09 versus those with healthy gingiva. The medication regimen administered in both groups of the study was comparable. CONCLUSION: No association between the IL-6 gene polymorphism and gingival overgrowth was revealed in kidney transplant patients administered cyclosporin A as a principal immunosuppressive agent.     

Analysis of the association of IL1B(C-511T) polymorphism with dental implant loss and the clusterization phenomenon

Objectives: Endosteous dental implants consist in the treatment of choice to replace tooth loss. The knowledge that implant loss tends to cluster in subsets of individuals may indicate that host immune‐inflammatory response is influenced by genetic factors. Interleukin‐1 (IL‐1) is a key mediator of inflammatory processes and functional polymorphisms in IL1 gene could be candidate genetic risk factors to study susceptibility to implant failure. The objective of this study was to investigate the association between IL1B (C‐511T) genetic polymorphism and dental implant loss in a Brazilian population and its influence in the clusterization phenomenon. Material and methods: The sample composed of 277 unrelated, both gender, mean age 53.63 ± 11.14 years individuals, divided into test group – 92 subjects with implant loss, and control group – 185 subjects with no implant loss. Patients' socioeconomic profile and clinical variables were investigated. Genomic DNA from oral mucosa was analyzed by polymerase chain reaction–restriction fragment length polymorphism. Results: There was significant difference between the groups in medical treatment (P=0.040), edentulism (P=0.019), and mean number of placed implants (P=0.001). There was difference between groups with and without implant loss neither considering genotypes (P=0.279) nor alleles (P=0.168) for IL1B (C‐511T) polymorphism. When individuals showing up to one implant failure (n=254) were investigated vs. patients presenting multiple implant loss (n=23), no difference was either observed between groups for genotype (P=0.083) and allele (P=0.838) frequencies. Conclusions: The borderline association of the study polymorphism with implant loss suggests further IL1 haplotype analysis to elucidate the global involvement of IL‐1 proteins in the modulation of the osseointegration process. To cite this article:
Dirschnabel AJ, Alvim‐Pereira F, Alvim‐Pereira CC, Bernardino JF, Rosa EAR, Trevilatto PC. Analysis of the association of IL1B(C‐511T) polymorphism with dental implant loss and the clusterization phenomenon.
Clin. Oral Impl. Res. 22 , 2011; 1235–1241
doi: 10.1111/j.1600‐0501.2010.02080.x     

Interleukin-6 receptor gene polymorphisms and periodontitis in a non-smoking Japanese population

AIM: The indispensable role of interleukin-6 receptor (IL-6R) in regulating IL-6 responses has been clearly established. We have previously reported that IL6R polymorphisms strongly influenced the serum levels of soluble IL-6R. In this study, we investigated the association between these genetic variations and periodontitis. MATERIAL AND METHODS: Among the seven novel IL6R single-nucleotide polymorphisms (SNPs) reported, we genotyped two important sites: the +48892 A/C in exon 9 and the -183 G/A in the promoter region. The SNP in exon 9 results in Asp-->Ala substitution in the proteolytic cleavage site of IL-6Ralpha. In total, 212 periodontitis cases and 210 healthy controls were genotyped using polymerase chain reaction, restriction fragment length polymorphisms and direct sequencing methods. RESULTS: Analysis of the genotype distribution of the +48892 A/C SNP in periodontitis patients and in controls revealed a suggestive association with aggressive (p = 0.04) and chronic periodontitis (p = 0.04). In addition, the carriage rate for the A allele was significantly higher in chronic periodontitis patients [p = 0.02, odds ratio (OR) = 2.25]. No association was found in the -183 G/A SNP. The two markers were in linkage disequilibrium (LD) (|D'| = 0.53). CONCLUSION: The IL6R+48892 A/C polymorphism could act as a risk factor for periodontitis; however, further association and biological studies are needed.     

Analysis of tumor necrosis factor-alpha, transforming growth factor-beta, interleukin-10, IL-6, and interferon-gamma gene polymorphisms in patients with chronic periodontitis

BACKGROUND: Cytokine gene polymorphisms may have an impact on the susceptibility to and progression of chronic periodontitis. In this study, we analyzed the -1082 interleukin-10 (IL-10), -308 tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta 1 (TGF-beta1) (codons 10 and 25), -174IL-6, and +874 interferon-gamma (IFN-gamma) gene single-nucleotide polymorphisms in a cohort of patients with chronic periodontal disease. METHODS: The diagnosis was made on the basis of standardized clinical and radiographic criteria. A total of 122 adult patients with chronic periodontitis and 114 unrelated, ethnically and age-matched white control subjects were genotyped by a polymerase chain reaction-sequence-specific primer. RESULTS: The number of individuals carrying the -174IL-6 CC genotype was significantly higher in the group of patients than in the control group (odds ratio [OR] = 1.896; 95% confidence interval [CI] = 1.106 to 3.250; P = 0.0283). The TGF-beta1 (codon 25) GG (Arg(25)/Arg(25)) genotype was detected more frequently in control subjects than in periodontitis patients (OR = 0.459; 95% CI = 0.230 to 0.920; P = 0.0421). CONCLUSION: The -174IL-6 and TGF-beta1 (codon 25) single-nucleotide polymorphisms are associated with susceptibility to chronic periodontitis in the population studied.     

Porphyromonas gingivalis HmuY‐Induced Production of Interleukin‐6 and IL‐6 Polymorphism in Chronic Periodontitis

Background: In chronic periodontitis (CP), the gene polymorphism of interleukin‐6 (IL‐6) to 174C/G has been associated with the altered production of this cytokine. The aim of this pilot study is to compare the allelic and genotypic frequencies in patients with CP with control individuals without periodontitis (NP) and to measure the production of IL‐6 by whole blood cells stimulated with Porphyromonas gingivalis HmuY protein. Methods: DNA was isolated from peripheral blood cells of 49 patients with CP and 60 control individuals classified as NP, and genotyping was performed by polymerase chain reaction using sequence‐specific primers. Whole blood cells from 29 patients with CP and 30 control individuals were stimulated for 48 hours with HmuY, and IL‐6 levels were measured using enzyme‐linked immunosorbent assay. Results: The proportion of individuals carrying the G allele at position –174 of the IL‐6 gene was higher in the group with CP (85.7%) than in the normal control group (73.3%; P <0.03). P. gingivalis HmuY‐induced production of IL‐6 was higher in the group with CP (P <0.05). Conclusions: Our findings suggest that P. gingivalis HmuY may be associated with increased IL‐6 production during CP. Furthermore, patients with periodontitis and individuals with higher HmuY‐induced production of IL‐6 show a high frequency of the G allele at position –174.     

Cytokine gene polymorphisms in periodontal disease: a meta-analysis of 53 studies including 4178 cases and 4590 controls

Aim: We conducted a systematic review and a meta-analysis, in order to investigate the potential association of cytokine gene polymorphisms with either aggressive or chronic periodontal disease.
Material and Methods: A comprehensive literature search was performed. We retrieved a total of 53 studies summarizing information about 4178 cases and 4590 controls. Six polymorphisms were included in our meta-analysis which are the following: IL-1A G[4845]T, IL-1A C[−889]T, IL-1B C[3953/4]T, IL-1B T[−511]C, IL-6 G[−174]C and TNFA G[−308]A. Random effect methods were used for the analysis. We calculated the specific odds ratios along with their 95% confidence intervals to compare the distribution of alleles and genotypes between cases and controls.
Results and Conclusions: Using random effect methods we found statistically significant association of IL-1A C[−889]T and IL-1B C[3953/4]T polymorphisms with chronic periodontal disease without any evidence of publication bias or significant statistical heterogeneity. A weak positive association was also found concerning IL-1B T[−511]C and chronic periodontal disease. No association was found for all the cytokines examined as far as the aggressive form of the disease is concerned. Future studies may contribute to the investigation of the potential multigenetic predisposition of the disease and reinforce our findings.     

白细胞介素-6基因多态性与种植体周围组织疾病的相关性研究

目的    探讨白细胞介素-6基因的174位点（IL-6-174位点）单核酸多态性与种植体周围组织疾病的关系及其临床意义。方法    选择2017年10月至2019年2月在辽宁省人民医院口腔科诊治的健康种植体周围组织患者（健康种植体组）和种植体周围组织疾病患者（种植体周围组织疾病组）各80例,刮取患者口腔颊黏膜拭子,采用PCR-Sanger基因测序方法分析两组IL-6-174位点多态性的基因型和等位基因频率分布差异,探讨其与种植体周围组织疾病的相关性。结果　IL-6-174位点的3种基因型和等位基因分布频率在种植体周围组织疾病组与健康种植体组之间的差异均有统计学意义（基因型：χ2 = 6.262,P = 0.044;等位基因：χ2 =5.033,P = 0.025）;其中,CC基因型和C等位基因的OR值分别为4.03（95%CI为2.861 ~ 5.677）和1.823（95%CI为1.706 ~ 1.967）。进一步分析显示,3种基因型和等位基因分布频率在种植体周围炎组与健康种植体组之间的差异有统计学意义（基因型：χ2 = 7.741,P = 0.021;等位基因：χ2 = 6.711,P = 0.010）,但在种植体周围黏膜炎组与健康种植体组患者之间不存在IL-6-174G/C基因多态性的差异（基因型χ2 = 2.008,P = 0.366;等位基因χ2 =0.817,P = 0.366）。结论    IL-6-174基因位点的多态性与种植体周围组织疾病的易感性具有相关性。