A Study On The Association Between TNF Alpha Gene Polymorphisms And Type2 Diabetes Mellitus With Chronic Periodontitis

ObjectiveThe studies reported here were to detect the TNF alpha genetic polymorphism of the patients of type 2 diabetes mellitus with chronic periodontitis, periodontitis without any systemic diseases and healthy controls.We compared the frequency of the case and control group to know the difference among them. We also studied the clinical index ofall the group to know if allele would affect the development of periodontitis.Materials and MethodsCase groups were consisted of 112 patients with moderate,severe type 2 diabetes mellitus with chronic periodontitis,99 patients with moderate,severe periodontitis without any systemic disease,50 subjects of age and gender matched with healthy periodontal conditions were enrolled. Clinical parametes were measured and recorded including probing depth(PD), clinical attachment loss(CAL), bleeding index(BI), and tooth movement(TM). Genomic DNA from peripheral venous blood was extracted with saturant sodium chloride,TNF-a-308 amplified with specific primers then digested with restriction endonuclease.The polymorphism in this genotype was examined after electrophoresis on agarose gel and ethidium dromide staining. The differences between the case groups and healthy group were analysed by chi square test,the differences in clinical index among groups which taken different allele were performed by mean square analysis.Results1.The differences of TNF-a-308 allele frequence between case group and control groupof all the groups, TNF-a-308 alleleⅠ/Ⅰwas most frequency found, TNF-a-308 alleleⅠ/Ⅱwas more found,TNF-α-308 alleleⅡ/Ⅱwas the least found.We had studied TNF一α-308 alleleⅡfrequence and found that there were significant differences among DM group,CP group and healthy group.We divided DM and CP groups into moderate and severe groups.The frequencies of TNF-α-308 alleleⅡwere 0.26 and 0.28 in severe and moderate DM group,however the frequencies of TNF-α-308 alleleⅡwere 0.14 and 0.15 in severe and moderate CP group.There were significant differences between severe DM group and severe,moderate CP group,between moderate DM group and severe,moderate group.But there were no difference in DM groups and CP groups.2.The clinical indexs of different alleles in case groupFor the patients who took TNF-α一308 alleleⅡin DM group,the probing depth,clinical attachment loss,bleeding index and tooth movement were 3.15士1.27mm, 3.48士1.63mm,1.59±0.66,1.22±0.49; in CP group the above indexs were 2.56±1.11mm,2.62±1.26mm,1.57±0.64,0.94±0.47.For the patients who only took TNF-α-308 alleleⅠin DM group,the probing depth,clinical attachment loss,bleeding index and tooth movement were 2.83±1.06mm,2.96±1.1mm,1.58±0.68,1.20±0.48: in CP group the above indexs were 2.22mm±1.35,2.56mm±1.83,1.58±0.62,0.92±0.41. We found that the probing depth and clinical attachment loss of the patients who took TNF-α-308 alleleⅡwas singnificant higher than the patients who took TNF-α-308 alleleⅠin DM group,however, the bleeding index,tooth movement between the patient who took TNF-α-308 alleleⅡand only alleleⅠwas no significant difference.In CP group,the probing depth,clinical attachment loss of the patients who took TNF-α-308 allele 11 was singnificant higher than the patients who took TNF-α-308 alleleⅠ,bleeding index,tooth movement between the patients who took TNF-α-308 alleleⅡand only alleleⅠwas no significant difference.Conclusions1.It suggested that TNF-α-308 alleleⅡmight raise the susceptivity of periodontitis in population.2.TNF-α-308 alleleⅡmay play an important role in synergistic reaction of periodontitis and type 2 diabetes.3.The existence of TNF-a-308 alleleⅡmay correlate with the periodontium destruction level of the patients of type 2 diabetes mellitus with chronic periodontitis.4 The polymorphisms of TNF alpha gene was problely different in different population and regions.