title: Association among interleukin-6 gene polymorphisms, type 2 diabetes mellitus, and chronic periodontitis: a pilot study.
abstract: OBJECTIVE
  The purpose of this pilot study was to determine the association between single nucleotide polymorphisms (-174 G>C) in the interleukin-6 (IL-6) gene with chronic periodontitis (CP) and type 2 diabetes mellitus (T2DM) in south Indian population.
  
  
  METHODS
  Genomic DNA was obtained from the white blood cells of 30 patients with T2DM, 30 patients with CP, 30 patients with T2DM with CP, and 30 controls. DNA was amplified using polymerase chain reaction with specific primers flanking the locus -174 of the IL-6 gene and further genotyped using the restriction fragment length polymorphism method. The genotype distribution and allele frequencies between the study groups were determined using χ2-test. The relative risk was estimated with a 95% confidence interval.
  
  
  RESULTS
  The CP group (26.7%) displayed a greater percentage of GC genotype (P = 0.026) when compared to the control group (3.3%). A statistically-significant difference in the allele frequencies was found between the control and CP group with the C-allele frequency being greater (0.13) in the CP group than normal controls (0.02).
  
  
  CONCLUSIONS
  The GC genotype was found to be the risk genotype and the C allele was found to be the risk allele for the development of CP.
authors.affiliation: Department of Oral and Maxillofacial Pathology, Ragas Dental College and Hospital, Chennai, India.
authors.forename: Loganathan
authors.initials: L
authors.lastname: Kavitha
authors.affiliation: Central Research Laboratory, Meenakshi Ammal Dental College and Hospital, Chennai, India.
authors.forename: Jayaseelan
authors.initials: J
authors.lastname: Vijayshree Priyadharshini
authors.affiliation: Department of Oral Pathology and Microbiology, Meenakshi Ammal Dental College and Hospital, Chennai, India.
authors.forename: Balasundaram
authors.initials: B
authors.lastname: Sivapathasundharam
mesh_terms: D000328:Adult; D000368:Aged; D055113:Chronic Periodontitis / Q000235:genetics*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D005787:Gene Frequency; D006801:Humans; D007194:India; D015850:Interleukin-6 / Q000235:genetics*; D008875:Middle Aged; D010865:Pilot Projects; D020641:Polymorphism, Single Nucleotide
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6
keywords: chronic periodontitis; interleukin-6 gene; polymerase chain reaction; single nucleotide polymorphism; type 2 diabetes mellitus