Lack of Association between Interleukin-1β Gene Polymorphism (rs16944) and Chronic Periodontitis: From a Case-Control Studies to an Updated Meta-Analysis

Associations among gene polymorphisms, crestal bone loss, and bone mineral density in patients receiving dental implants

Objectives

Interleukin 1 (IL-1) and interleukin 6 (IL-6) gene polymorphisms have been suggested to be responsible for diminished bone mineral density (BMD) and high crestal bone loss (CBL) in some individuals. However, the effects of systemic BMD on variations in peri-implant CBL are unclear. Hence, this study was aimed at investigating the association of IL-1 and IL-6 gene polymorphisms with systemic BMD and CBL around dental implants.

Methods

A total of 190 participants undergoing dental implantation in the mandibular posterior region were selected according to predetermined selection criteria and divided into a normal BMD group (NBD, 93 participants, T-score ≥ -1) and low BMD group (LBD, including both osteoporosis and osteopenia, 97 participants, T-score < -1 standard deviation) according to the BMD of the right femoral neck, measured with dual-energy X-ray absorptiometry. Dental implants were placed through the standard surgical protocol, and CBL was calculated after 6 months with cone beam computed tomography scans before second-stage surgery. Genotyping was performed on all participants for IL-1A-889 A/G, IL-1B-511G/A, IL-1B+3954, and IL-6-572 C/G gene polymorphisms.

Results

The demographic and clinical characteristics of the participants in both groups were compared with t-test and chi-square test (χ2). The associations of NBD and LBD with the different genotypes and CBL was determined with odds ratios, and p < 0.05 was considered statistically significant. The frequency of IL-1B-511AA and IL-6-572 GG genotypes was significantly higher in LBD than in NBD (p < 0.05). In LBD, the IL-1B-511 AA (AA vs GA + GG; p ≤ 0.001) and IL-6-572 GG (GG vs CC + GC; p = 0.001) genotypes were significantly associated with higher peri-implant CBL.

Conclusions

Individuals with the IL-1B-511 AA or IL-6-572 GG genotype had elevated risk of osteoporosis/osteopenia and were more susceptible to CBL around dental implants.

Association of interleukin-1, interleukin-6, collagen type I alpha 1, and osteocalcin gene polymorphisms with early crestal bone loss around submerged dental implants: A nested case control study

STATEMENT OF PROBLEM

The reason for variations in peri-implant early crestal bone loss is unclear but may be due to genetic differences among individuals.

PURPOSE

The purpose of this nested case control study was to investigate the association of single-nucleotide polymorphisms of interleukin-1, interleukin-6, collagen type I alpha1, and osteocalcin genes to early crestal bone loss around submerged dental implants.

MATERIAL AND METHODS

Dental implants were placed in the mandibular posterior region (single edentulous space) of 135 participants selected according to predetermined selection criteria. Bone mineral density measurement by using dual energy X-ray absorptiometry, cone beam computed tomography scans at the baseline and after 6 months, and interleukin-1A-889 A/G (rs1800587), interleukin-1B-511 G/A (rs16944), interleukin-1B+3954 (rs1143634), interleukin-6-572 C/G (rs1800796), collagen type I alpha1 A/C (rs1800012), and osteocalcin C/T (rs1800247) genotyping were performed in all participants. Early crestal bone loss measured around dental implants was used to group participants into clinically significant bone loss (BL)>0.5 mm and clinically nonsignificant bone loss (NBL)≤0.5 mm. Early crestal bone loss was calculated as the mean of the difference of bone levels at the baseline and bone levels after 6 months as measured with cone beam computed tomography scans. The obtained data for basic characteristics, early crestal bone loss, and genotyping were tabulated and compared by using a statistical software program (α=.05).

RESULTS

AA genotype and the A allele frequency of interleukin-1B-511 and GG genotype and the G allele frequency of interleukin-6-572 were significantly higher in BL than in NBL (P<.05). Multiple logistic analysis suggested that interleukin-1B-511 AA/GG+AG and interleukin-6-572 GG/CC+CG genotype expression were significantly associated with early crestal bone loss (AA/GG+AG; P=.014, GG/CC+CG; P=.047) around dental implants. Other risk factors were not significantly different (P>.05).

CONCLUSIONS

Of the genes studied, individuals with interleukin-1B-511 AA (rs16944) or interleukin-6-572 GG (rs1800796) genotype had higher susceptibility to early crestal bone loss around dental implants.

The relationship between gestational diabetes mellitus and interleukin 1beta gene polymorphisms in southwest of China

Gestational diabetes mellitus (GDM) is a kind of chronic inflammatory condition with carbohydrate metabolism disorder. Interleukin-1beta (IL-1β) plays an important role in inflammatory response, but its role in GDM development remains unknown. The aim of this study was to analyze the association between Interleukin 1beta (IL1B) rs1143623 and rs16944 polymorphisms and susceptibility to GDM.In total, 300 pregnant women with GDM and 261 healthy pregnant women were included in the study. In both groups, single nucleotide polymorphism (SNP) rs1143623 and rs16944 were analyzed by using snapshot technology. IL-1β serum values were determined by ELISA.Serum IL-1β levels involvement in GDM development. According to the results, we found the association between the IL1B rs1143623 polymorphism and susceptibility to GDM. In further analysis, IL1B rs1143623 GG genotype had a higher level of total cholesterol (TCHO) and lower level of high density lipoprotein (HDL) in GDM patients compared with the CC/GC genotypes. However, there were no statistically significant difference between the GDM and healthy control groups in terms of rs16944 polymorphism.Our results indicated that rs1143623 in IL1B gene may lead to GDM in the southwest of china. However, no significant difference was found between GDM and rs16944. The rs1143623 genotype may significantly impact the fat metabolism, especially the levels of TCHO and HDL. We believe that our findings will contribute to understanding of the etiology and possible novel prognostic markers for GDM.

Genetic polymorphisms in the Interleukins IL1B, IL4, and IL6 are associated with concomitant periodontitis and type 2 diabetes mellitus in Brazilian patients

OBJECTIVE

To assess whether single nucleotide polymorphisms (SNPs) in the IL10, IL1A, IL1B, IL4, TNFA, IL6, OPG, RANK, and RANKL genes, "classically" related with periodontitis, could be associated with susceptibility to T2DM, and also with both diseases concomitantly.

BACKGROUND

There are common pathogenic mechanisms in type 2 diabetes mellitus (T2DM) and periodontitis, but the knowledge of the genetic aspect of this is limited. In patients affected by concomitant T2DM and periodontitis, whose incidence is increasing, there is scarce information regarding the gene-phenotype association, including whether there are genes able to influence both diseases as comorbidities.

METHODS

Periodontal clinical parameters and biochemical profile (Insulin, Fasting Glycemia, HbA1c, Triglycerides, Total Cholesterol, HDL-cholesterol, and LDL-cholesterol) data were obtained from 894 individuals divided into following three groups: Healthy (H; n = 347), Periodontitis (P; n = 348), and Periodontitis + T2DM (P + T2DM; n = 199). DNA from oral epithelial cells was collected for genotyping. Associations between SNPs and pathologies were tested by multiple logistic regression models, adjusting for age, sex, and smoking habits. We also investigated whether there are sex or smoking effects of each SNP in these phenotypes.

RESULTS

The rs1143634-GA (IL1B) SNP showed significantly less likely to develop P + T2DM for all population and mainly for women (adjusted OR = 0.37, 95% CI = 0.16-0.88), while women carrying the rs224320 CT (IL4) were more susceptible to develop P + T2DM (adjusted OR = 1.81, 95% CI = 1.04-3.15). Men carrying the rs1800795-CC (IL6) genotype were less likely to develop T2DM (adjusted OR = 0.12, 95% CI = 0.02-0.70, P = .01).

CONCLUSIONS

Some SNPs in the IL1B, IL4, and IL6 genes demonstrated sex-influenced association with concomitant periodontitis and T2DM, increasing the evidence of a common genetic component between these diseases and contributing with the understanding of their common pathogenic mechanisms.