Genomewide association study on chronic periodontitis in Korean population: results from the Yangpyeong health cohort Hong K-W, Shin M-S, Ahn Y-B, Lee H-J, Kim H-D. Genomewide association study on chronic periodontitis in Korean population: results from the Yangpyeong health cohort. J Clin Periodontol 2015; 42: 703–710. doi: 10.1111/jcpe.12437. Abstract Aim: This study aims to locate the genes related to periodontitis through gen- ome-wide association study (GWAS) in Korean population. Methods: Total of 677 adults aged 44–88 years were recruited from the Yang- pyeong cohort in Korea. The participants did not have self-reported metabolic dis- eases, cardiovascular diseases or cancer. Periodontitis was assessed using alveolar bone loss from a digital panoramic radiograph and classified into three groups: nor- mal 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 single-nucleotide polymor- phisms (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 9 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 aetiology of periodontitis. Kyung-Won Hong 1,2 , Myung-Seop Shin 3 , Yoo-Been Ahn 3 , Hyun-Jin Lee 3 and Hyun-Duck Kim 3,4 1 Theragen Etex Bio Institute, Suwonsi, Gyeonggi-do; 2 Division of Biomedical Informatics, Center for Genome Science, National Institute of Health, KCDC, Cheongju-si, Chungbuk; 3 Department of Preventive and Social Dentistry; 4 Dental Research Institute, School of Dentistry, Seoul National University, Daehak-ro, Seoul, Korea Drs. Hong and Shin are co-first authors who contributed equally to this work. Key words: epidemiology; genome-wide association studies; Korean; periodontitis; single-nucleotide polymorphisms Accepted for publication 10 May 2015 Periodontitis is a chronic inflamma- tory disease caused by bacterial infection of the supporting tissues around the teeth (Haffajee & Socransky 1994, Page et al. 1997). Pathologic destruction of alveolar bone due to periodontitis is an irre- versible process and periodontitis is one of the major causes of tooth loss Conflict of interest and sources of funding statement The authors report no conflicts of interest related to this study. This study was provided with biospecimens and data from the Korean Genome Analysis Project (4845-301), the Korean Gen- ome and Epidemiology Study (4851-302) and Korean Biobank Project (4851-307, KBP-2014-15) that were supported by the Korea Center for Disease Control and Prevention, Republic of Korea. This work was supported by a grant from Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2013-062881) and the NRF Grant, through the Oromaxillofacial Dysfunction Research Center for the Elderly (No. 2014-050477) at Seoul National University in Korea. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd 703 J Clin Periodontol 2015; 42: 703–710 doi: 10.1111/jcpe.12437