Genomewide association study on the severity of periodontitis in Korean population: results from the Yangpyeong health cohort

Abstract

Objective: This study aims to locate the genes related to periodontitis through genome-wide association study (GWAS) in Korean population. Methods: Total of 677 adults aged 44-88 years were recruited from the Yangpyeong cohort in Korea. The participants did not have self-reported metabolic diseases, cardiovascular diseases or cancer. Periodontitis was assessed using alveolar bone loss from a digital panoramic radiograph and classified into three groups: normal to mild, moderate and severe periodontitis. DNA from blood samples were genotyped using the Illumina Human 1M-duo Beadchip. Multivariable logistic regression analysis in PLINK was applied to examine the SNPs related to periodontitis after controlling for various confounders. Results: Associations of three SNPs suggested TENM2 (rs4242220) and LDLRAD4 (rs12969041, rs2027756) as putative risk genes of chronic periodontitis (p-values< 1 × 10-5). The odds ratio (95% confidence interval [CI]) of TENM2 was 0.53 (0.40-0.70) for moderate periodontitis and that of LDLRAD4 was 2.86 (1.92-4.27) for severe periodontitis. Two nonsynonymous SNPs of protein coding region and seven SNPs selected from previous reports showed nominal association. Conclusion: Our GWAS supports a previously reported gene of TENM2 and newly suggests LDLRAD4. These two genes role on lipid metabolism may play a part in the molecular etiology of periodontitis.