Current Status, Challenges, Policies, and Bioethics of Biobanks

Many biobanks were established as biorepositories for biomedical research, and a number of biobanks were founded in the 1990s. The main aim of the biobank is to store and to maintain biomaterials for studying chronic disease, identifying risk factors of specific diseases, and applying personalized drug therapies. This report provides a review of biobanks, including Korean biobanks and an analysis of sample volumes, regulations, policies, and ethical issues of the biobank. Until now, the top 6 countries according to the number of large-scale biobanks are the United Kingdom, United States, Sweden, France, the Netherlands, and Italy, and there is one major National Biobank of Korea (NBK) and 17 regional biobanks in Korea. Many countries have regulations and guidelines for the biobanks, and the importance of good management of biobanks is increasing. Meanwhile, according to a first survey of 456 biobank managers in the United States, biobankers are concerned with the underuse of the samples in their repositories, which need to be advertised for researchers. Korea Biobank Network (KBN) project phase II (2013-2015) was also planned for the promotion to use biospecimens in the KBN. The KBN is continuously introducing for researchers to use biospecimens in the biobank. An accreditation process can also be introduced for biobanks to harmonize collections and encourage use of biospecimens in the biobanks. KBN is preparing an on-line application system for the distribution of biospecimens and a biobank accreditation program and is trying to harmonize the biobanks.

Association of an Anti-inflammatory Cytokine Gene IL4 Polymorphism with the Risk of Type 2 Diabetes Mellitus in Korean Populations

Chronic inflammation has been implicated as one of the important etiological factors in insulin resistance and type 2 diabetes mellitus (T2DM). To investigate the role of anti-inflammatory cytokines in the development of T2DM, we conducted a case-control study to assess the association between IL4/IL4R polymorphisms and disease risk. We firstly identified single nucleotide polymorphisms (SNP) at IL4 and IL4RA loci by sequencing the loci in Korean participants. Case-control studies were conducted by genotyping the SNPs in 474 T2DM cases and 470 non-diabetic controls recruited from community-based cohorts. Replication of the associated signals was performed in 1,216 cases and 1,352 controls. We assessed effect of IL4-IL4RA interaction on T2DM using logistic regression method. The functional relevance of the SNP associated with disease risk was determined using a reporter expression assay. We identified a strong association between the IL4 promoter variant rs2243250 and T2DM risk (OR=0.77; 95% CI, 0.67~0.88; p=1.65x10-4 in the meta-analysis). The reporter gene expression assay demonstrated that the presence of rs2243250 might affect the gene expression level with ~1.5-fold allele difference. Our findings contribute to the identification of IL4 as a T2D susceptibility locus, further supporting the role of anti-inflammatory cytokines in T2DM disease development.

Prevalence of Atrial Fibrillation in Middle-Aged People in Korea: The Korean Genome and Epidemiology Study

BACKGROUND AND OBJECTIVES: The prevalence of atrial fibrillation (AF), the most common sustained arrhythmia, is expected to rise with the aging population, but very few studies have reported on the prevalence and risk factors of AF in Korea. SUBJECTS AND METHODS: We analyzed 10,012 Korean adults (4,750 men and 5,262 women), 40-69 years old, who were enrolled in the Korean Genome and Epidemiology Study. AF was diagnosed by single electrocardiogram recording in a baseline survey (2001-2003). RESULTS: The estimated prevalence of AF was 0.4% {95% confidence interval (CI), 0.28-0.52} in adults 40-69 years old, and increased to 1.0% in individuals 60-69 years old. The prevalence rate for men (0.6%) was higher than for women (0.2%) across all age groups. In multiple logistic regression analysis, AF was significantly associated with old age {odds ratio (OR), 8.15; 95% CI, 3.06-21.71}, male gender (OR, 4.04; 95% CI, 1.90-8.61), diabetes mellitus (OR, 2.15; 95% CI, 1.05-4.44), and congestive heart failure (OR, 14.11; 95% CI, 2.56-77.70). Obesity, however, did not show an association with AF. CONCLUSION: The prevalence of AF in Korean adults aged 40-69 years is approximately 0.4%, lower than that in Western populations. Age, male gender, diabetes, and heart failure are associated with AF. Further research in a larger population is necessary to verify for our results.

Association of lipoprotein lipase (LPL) single nucleotide polymorphisms with type 2 diabetes mellitus

The etiology and pathogenesis of type 2 diabetes mellitus (T2DM) are not completely understood although it is often associated with other conditions such as obesity, hypertension, and dyslipidemia. Lipoprotein lipase (LPL) is a key enzyme in human lipid metabolism that facilitates the removal of triglyceride-rich lipoproteins from the bloodstream. LPL hydrolyzes the core of triglyceride-rich lipoproteins (chylomicrons and very low density lipoprotein) into free fatty acids and monoacylglycerol. To gain insight into the possible role of LPL in T2DM, nine single nucleotide polymorphisms (SNPs) of LPL were analyzed for the association with T2DM using 944 unrelated Koreans, including 474 T2DM subjects and 470 normal healthy controls. Of the nine LPL SNPs we analyzed, a significant association with multiple tests by the false discovery rate (FDR) was observed between T2DM and SNP rs343 (+13836C>A in intron 3). SNP rs343 was also marginally associated with some of T2DM-related phenotypes including total cholesterol, high density lipoprotein cholesterol (HDLc), and log transformed glycosylated hemoglobin in 470 normal controls, although no significant association was detected by multiple tests. In total, our results suggest that the control of lipid level by LPL in the bloodstream might be an important factor in T2DM pathogenesis in the Korean population.

Dietary Patterns and Prevalence Odds Ratio in Middle-aged Adults of Rural and Mid-size City in Korean Genome Epidemiology Study

Recently, dietary pattern analysis was emerged as an approach to examine the relationships between diet and risk of chronic diseases. This study was to identify groups with population who report similar dietary pattern in Korean ge-nome epidemiology study (KoGES )and association with several chronic diseases. The cohort participants living in Ansung and Ansan (Gyeonggi province )were totally 10,038. Among those, 6,873 subjects with no missing values in food frequency questionnaire were included in this analysis. After combining 103 food items into 17 food groups, 4 dietary factors were obtained by factor analysis based on their weights. Factor 1 showed high factor loadings in vege-tables, mushrooms, meats, fish, beverages, and oriental-cereals. Factor 2 had high factor loadings in vegetables, fruits, fish, and factor 3 had high factor loadings in cereal-oriental, cerial-western and snacks. Factor 4 showed positive high factor loadings in rice and Kimchi and negative factor loadings in mushrooms and milk and dairy products. Using factor scores of four factors, subjects were classified into 3 clusters by K-means clustering. We named those 'Rice and Kimchi eating' group, 'Contented eating' group, and 'Healthy and light eating' group depending on their eating cha-racteristics. 'Rice and Kimchi eating' group showed high prevalence in men, farmers and 60s. 'Contented eating' group and 'Healthy and light eating' group had high prevalence in women, people living in urban area (Ansan Citizen ), with high-school education and above, and a monthly income of one million won and more. 'Contented eating' group appeared lower distribution proportion in the sixties and 'Healthy and light eating' group does higher in the fifties. 'Contented eating' versus 'Rice and Kimchi eating', odds ratio for hypertension, diabetes, metabolic syndrome and obesity significantly decreased after adjusting age and sex (OR =0.64, 0.73, and 0.85 respectively, 95% CI ). Although our results were from a cross-sectional study, these imply that the dietary patterns were related to diseases.