A genome-wide association scan reveals novel loci for facial traits of Koreans.

DNA-based prediction of externally visible characteristics (EVC) with SNPs is one of the research areas of interest in the forensic field. Based on a previous study performing GWAS on facial traits in a Korean population, herein, we present results stemming from GWA analysis with KoreanChip and novel genetic loci satisfying genome-wide significant level. We discovered a total of 20 signals and 12 loci were found to have novel associations with facial traits, including six loci located in intergenic regions and six loci located at UBE2O, HECTD2, CCDC108, TPK1, FCN2, and FRMPD1. Additionally, we performed a polygenic score analysis for 33 distance-related traits in facial phenotyping and determined genetic relationships between facial traits and SNPs using the GCTA program. The results of the current study offer an understanding of how facial morphology is influenced by complex genetic structures and provide insights into forensic investigation and population genetics.

Effect of genetic variants in UBE2O and TPK1 on facial morphology of Koreans.

Human face is a highly heritable and complex trait. Many genome-wide analyses have identified genetic variants influencing facial morphology. Genome-wide association studies (GWASs) investigating facial morphologies of different populations provide a comprehensive insight into the genetic basis of the human face. Here, we report a GWAS of normal facial variation in Koreans using an array optimized for the Korean population (KoreanChip). We found that novel genetic variants encompassing four loci reached the genome-wide significance threshold. They include LOC107984547, UBE2O, TPK1, and LINC01148 loci associated with facial angle, brow ridge protrusion, nasal height, and eyelid curvature. Our results also validated previously published genetic loci, including FAT4, SOX9, and TBX3 loci. All confirmed genetic variants showed phenotypic differences involving each facial trait based on the effect of the minor allele. The present study highlights genetic signals associated with normal human facial variation and provides candidates for functional studies. Key points: GWAS of normal facial variation in the Korean population was conducted using a Korean genome chip.Previously reported genetic signals associated with FAT4, SOX9, and TBX3 loci were replicated in the Korean populations.Genetic signals in UBE2O and TPK1 loci were identified as novel variants for corresponding facial features.

The UGT1A9*22 genotype identifies a high-risk group for irinotecan toxicity among gastric cancer patients.

Several studies have shown associations between irinotecan toxicity and UGT1A genetic variations in colorectal and lung cancer, but only limited data are available for gastric cancer patients. We evaluated the frequencies of UGT1A polymorphisms and their relationship with clinicopathologic parameters in 382 Korean gastric cancer patients. Polymorphisms of UGT1A1*6, UGT1A1*27, UGT1A1*28, UGT1A1*60, UGT1A7*2, UGT1A7*3, and UGT1A9*22 were genotyped by direct sequencing. In 98 patients treated with irinotecan-containing regimens, toxicity and response were compared according to the genotype. The UGT1A1*6 and UGT1A9*22 genotypes showed a higher prevalence in Korean gastric cancer patients, while the prevalence of the UG1A1*28 polymorphism was lower than in normal Koreans, as has been found in other studies of Asian populations. The incidence of severe diarrhea after irinotecan-containing treatment was more common in patients with the UGT1A1*6, UGT1A7*3, and UGT1A9*22 polymorphisms than in controls. The presence of the UGT1A1*6 allele also showed a significant association with grade III-IV neutropenia. Upon haplotype and diplotype analyses, almost every patient bearing the UGT1A1*6 or UGT1A7*3 variant also had the UGT1A9*22 polymorphism, and all severe manifestations of UGT1A polymorphism-associated toxicity were related to the UGT1A9*22 polymorphism. By genotyping UGT1A9*22 polymorphisms, we could identify high-risk gastric cancer patients receiving irinotecan-containing chemotherapy, who would experience severe toxicity. When treating high-risk patients with the UGT1A9*22 polymorphism, clinicians should closely monitor them for signs of severe toxicity such as intense diarrhea or neutropenia.

Regulation of CIRP by genetic factors of SP1 related to cold sensitivity.

Cold-inducible RNA-binding-protein (CIRP) is a cold shock protein that plays a protective role in genotoxic stress response. CIRP modulates inflammation in human diseases, inhibits cell proliferation, and protects cells from genotoxic damage during cellular stress. The mild cold responsive element and specificity protein 1 (SP1) play a role in Cirp expression at low temperatures. Although previous studies have provided insights into the immune functions of SP1 or CIRP, the mechanisms by which CIRP and SP1 me diate inflammatory responses remain largely unknown. Therefore, in the current study, we examined whether Cirp expression is affected by genetic factors related to temperature sensitivity as well as under low temperature. We performed a genome-wide association study on cold sensitivity in 2,000 participants. Fifty-six genome-wide significant trait-locus pairs were identified (p<1×10-5, false discovery rate < 0.05). Among these variants, rs1117050 and rs11170510 had a strong linkage disequilibrium (r2 > 0.8) relationship and expression quantitative trait locus-associated signals with the nearest Sp1 gene. We confirmed that the minor alleles of rs11170510 and rs58123204 were associated with increased Sp1 expression. Additionally, Sp1 overexpression led to CIRP translocation from the nucleus to the cytoplasm. CIRP protein levels increased in serum samples that had minor alleles of rs11170510 and rs58123204. Levels of various pro-inflammatory cytokines were also significantly increased in human peripheral blood mononuclear cells with minor alleles of rs11170510 and rs58123204. These results suggest that genetic factors related to cold sensitivity regulate CIRP expression and function and provide valuable insights into prediction of potential diseases through analysis of inherent genetic factors in humans.

Systematic Analysis of the Molecular Mechanisms of Cold and Hot Properties of Herbal Medicines.

Effective treatments for patients experiencing temperature-related symptoms are limited. The hot and cold effects of traditional herbal medicines have been utilized to treat and manage these symptoms, but their molecular mechanisms are not fully understood. Previous studies with arbitrarily selected herbs and ingredients may have produced biased results. Here, we aim to systematically elucidate the molecular mechanisms of the hot and cold properties of herbal medicines through an unbiased large-scale investigation of herbal ingredients, their target genes, and the transcriptome signatures induced by them. Using data regarding 243 herbs retrieved from two herbal medicine databases, we statistically identify (R)-Linalool, (-)-alpha-pinene, peruviol, (L)-alpha-terpineol, and cymol as five new hot-specific ingredients that share a common target, a norepinephrine transporter. However, no significant ingredients are cold-specific. We also statistically identify 14 hot- and 8 cold-specific new target genes. Pathway enrichment analysis of hot-specific target genes reveals the associated pathways including neurotransmitter reuptake, cold-induced thermogenesis, blood pressure regulation, adrenergic receptor signaling, and cation symporter activity. Cold-specific target genes are associated with the steroid pathway. Transcriptome analysis also shows that hot herbs are more strongly associated with coagulation and synaptic transmission than cold herbs. Our results, obtained from novel connections between herbal ingredients, target genes, and pathways, may contribute to the development of pharmacological treatment strategies for temperature-related pain using medicinal plants.

PRICKLE1 × FOCAD Interaction Revealed by Genome-Wide vQTL Analysis of Human Facial Traits.

The human face is a highly complex and variable structure resulting from the intricate coordination of numerous genetic and non-genetic factors. Hundreds of genomic loci impacting quantitative facial features have been identified. While these associations have been shown to influence morphology by altering the mean size and shape of facial measures, their effect on trait variance remains unclear. We conducted a genome-wide association analysis for the variance of 20 quantitative facial measurements in 2,447 European individuals and identified several suggestive variance quantitative trait loci (vQTLs). These vQTLs guided us to conduct an efficient search for gene-by-gene (G × G) interactions, which uncovered an interaction between PRICKLE1 and FOCAD affecting cranial base width. We replicated this G × G interaction signal at the locus level in an additional 5,128 Korean individuals. We used the hypomorphic Prickle1 Beetlejuice (Prickle1 Bj ) mouse line to directly test the function of Prickle1 on the cranial base and observed wider cranial bases in Prickle1 Bj/Bj . Importantly, we observed that the Prickle1 and Focadhesin proteins co-localize in murine cranial base chondrocytes, and this co-localization is abnormal in the Prickle1 Bj/Bj mutants. Taken together, our findings uncovered a novel G × G interaction effect in humans with strong support from both epidemiological and molecular studies. These results highlight the potential of studying measures of phenotypic variability in gene mapping studies of facial morphology.

Circulating microRNAs as Potential Diagnostic Biomarkers for Poor Sleep Quality.

PURPOSE: Persistent poor sleep quality leads to impaired cognitive performance and an inability to perform daily activities. Biomarker-assisted diagnosis is important for the early treatment of poor sleep quality; however, diagnostic biomarkers for poor sleep quality remain unidentified. Circulating microRNAs (miRNAs) have been reported to be linked to the pathogenesis of poor sleep quality, indicating their possible role in sleep problem diagnosis. The present study aimed to identify potential miRNA biomarkers for poor sleep quality. PATIENTS AND METHODS: Differentially expressed serum miRNAs in patients with poor sleep quality and healthy controls (n=20) were analyzed via small RNA sequencing. Two-step quantitative RT-PCR in the two independent populations and receiver operating characteristic (ROC) analyses were used to validate the identified miRNAs. In silico analysis was then used to identify the target genes. RESULTS: Of the 59 circulating miRNAs identified via differential analysis, six were validated for differential expression by quantitative RT-PCR (n=60). Two of these six miRNAs, miR-4433b-3p and miR-619-5p, were reconfirmed in the second validation with an independent validation cohort (n=59). ROC analyses (n=40) revealed the probability of the two miRNAs as potential biomarkers with areas under the ROC curve (AUCs) of 0.81 and 0.70, respectively. The combined AUC was 0.86, which was much higher than that of each miRNA. Using in silico target gene analysis, the target genes of the two miRNAs were identified to be associated with the regulation of the circadian rhythm and inflammatory pathways. CONCLUSION: Our results revealed that miR-619-5p and miR-4433b-3p could be developed as potential diagnostic biomarkers for poor sleep quality. The combination of both miRNAs may be more effective than the use of the individual miRNA for sleep problem diagnosis.

Perception on genetic testing in Korean medicine doctors: A mobile-based survey.

BACKGROUND: Currently, genetic testing is widely used to understand individual characteristics. In Korea, genetic testing has been in use, but not actively in Korean Medicine (KM). To examine the perceptions of genetic testing, we performed online survey to Korean Medicine doctors (KMDs). METHODS: The survey was a mobile-based study that was developed by 6 survey specialists based on electronic database search results. The questionnaire consisted of 6 categories: general characteristics of respondents, understanding of genetic testing, demand for using genetic testing, application field and utilization level of genetic testing, limitations of genetic testing, and plans and necessary efforts to begin using genetic testing based on an 11-point Likert scale. RESULTS: With the response rate of 27.2% (n = 544), 46.9% of respondents answered that they understood the definition and mechanism of genetic testing. About 80% of KMDs responded that they would be willing to use genetic testing results; a notable reason for this was the need for more objective and evidence-based test results. KMDs recognized that genetic testing could not only provide personalized treatment and care, but also help communicate with patients. CONCLUSIONS: This study observed KMDs' perceptions of the potential clinical benefits of genetic testing. We confirmed that development of genetic testing technology, knowledge of their use, and new technology-friendly policies are essential for expanding the genetic testing technology in Korean medicine.

KRGDB: the large-scale variant database of 1722 Koreans based on whole genome sequencing.

Since 2012, the Center for Genome Science of the Korea National Institute of Health (KNIH) has been sequencing complete genomes of 1722 Korean individuals. As a result, more than 32 million variant sites have been identified, and a large proportion of the variant sites have been detected for the first time. In this article, we describe the Korean Reference Genome Database (KRGDB) and its genome browser. The current version of our database contains both single nucleotide and short insertion/deletion variants. The DNA samples were obtained from four different origins and sequenced in different sequencing depths (10× coverage of 63 individuals, 20× coverage of 194 individuals, combined 10× and 20× coverage of 135 individuals, 30× coverage of 230 individuals and 30× coverage of 1100 individuals). The major features of the KRGDB are that it contains information on the Korean genomic variant frequency, frequency difference between the Korean and other populations and the variant functional annotation (such as regulatory elements in ENCODE regions and coding variant functions) of the variant sites. Additionally, we performed the genome-wide association study (GWAS) between Korean genome variant sites for the 30×230 individuals and three major common diseases (diabetes, hypertension and metabolic syndrome). The association results are displayed on our browser. The KRGDB uses the MySQL database and Apache-Tomcat web server adopted with Java Server Page (JSP) and is freely available at http://coda.nih.go.kr/coda/KRGDB/index.jsp. Availability: http://coda.nih.go.kr/coda/KRGDB/index.jsp.

The age distribution of facial metrics in two large Korean populations.

Growth and alterations in craniofacial morphology have attracted interest in many fields of science, especially physical anthropology, genetics and forensic sciences. We performed an analysis of craniofacial morphology alterations by gender and ageing stage in Korean populations. We studied 15 facial metrics using two large Korean populations (1,926 samples from the Korea Medicine Data Center cohort and 5,643 samples from the Ansan-Ansung cohort). Among the 15 metrics, 12 showed gender differences and tended to change with age. In both of the independent populations, brow ridge height, upper lip height, nasal tip height, and profile nasal length tended to increase with age, whereas outer canthal width, right palpebral fissure height, left palpebral fissure height, right upper lip thickness, left upper lip thickness, nasal tip protrusion, facial base width, and lower facial width tended to decrease. In conclusion, our findings suggest that ageing (past 40 years of age) might affect eye size, nose length, upper lip thickness, and facial width, possibly due to loss of elasticity in the face. Therefore, these facial metric changes could be applied to individual age prediction and aesthetic facial care.

Convolutional neural network model to predict causal risk factors that share complex regulatory features.

Major progress in disease genetics has been made through genome-wide association studies (GWASs). One of the key tasks for post-GWAS analyses is to identify causal noncoding variants with regulatory function. Here, on the basis of >2000 functional features, we developed a convolutional neural network framework for combinatorial, nonlinear modeling of complex patterns shared by risk variants scattered among multiple associated loci. When applied for major psychiatric disorders and autoimmune diseases, neural and immune features, respectively, exhibited high explanatory power while reflecting the pathophysiology of the relevant disease. The predicted causal variants were concentrated in active regulatory regions of relevant cell types and tended to be in physical contact with transcription factors while residing in evolutionarily conserved regions and resulting in expression changes of genes related to the given disease. We demonstrate some examples of novel candidate causal variants and associated genes. Our method is expected to contribute to the identification and functional interpretation of potential causal noncoding variants in post-GWAS analyses.

Asymmetric dimethylarginine (ADMA) is identified as a potential biomarker of insulin resistance in skeletal muscle.

To unravel metabolic determinats of insulin resistance, we performed a targeted metabolomics analysis in Korean Children-Adolescent Cohort Study (KoCAS, n = 430). Sixty-seven metabolites were associated with insulin resistance in adolescents and the association also found in an adult population (KoGES, n = 2,485). Functional interactions of metabolites with gene/proteins using biological pathway with insulin resistance were not identified biological significance and regulatory effects of asymmetric dimethylarginine (ADMA). However, ADMA showed a higher association with adolescent obesity (P < 0.001) and adult diabetes (P = 0.007) and decreased after obesity intervention program. Functional studies in cellular and mouse models demonstrated that an accumulation of ADMA is associated with the regulation of obesity-induced insulin resistance in skeletal muscle. ADMA treatment inhibited dimethylarginine-dimethylaminohydrolase (DDAH) activity and mRNA expression in insulin resistance muscle cell. Moreover, the treatment led to decrease of phosphorylation of insulin receptor (IR), AKT, and GLUT4 but increase of protein-tyrosine phosphatase 1B (PTP1B). Accordingly, increased ADMA significantly inhibited glucose uptake in myotube cell. We suggest that accumulation of ADMA is associated with modulation of insulin signaling and insulin resistance. ADMA might expand the possibilities of new therapeutic target for functional and clinical implications in the control of energy and metabolic homeostasis in humans.

Cervical small cell neuroendocrine tumor mutation profiles via whole exome sequencing.

Cervical small cell neuroendocrine tumors (CSCNETs) are rare, aggressive neuroendocrine tumors (NETs). Reliable diagnostic and prognostic CSCNET markers are lacking, making diagnosis and prognosis prediction difficult, and treatment strategies limited. Here we provide mutation profiles for five tumor-normal paired CSCNETs using whole exome sequencing (WES). We expanded our assessment of frequently mutated genes to include publicly available data from 55 small intestine neuroendocrine tumors, 10 pancreatic neuroendocrine tumors, 42 small cell lung cancers, six NET cell lines, and 188 cervical cancers, along with our five CSCNETs. We identified 1,968 somatic mutations, including 1,710 missense, 106 nonsense, 144 splice site, 4 lncRNA, 3 nonstop, and 1 start codon mutation. We assigned functions to the 114 most frequently mutated genes based on gene ontology. ATRX, ERBB4, and genes in the Akt/mTOR pathway were most frequently mutated. Positive cytoplasmic ERBB4 immunohistochemical staining was detected in all CSCNET tumors tested, but not in adjacent normal tissues. To our knowledge, this study is the first to utilize WES in matched CSCNET and normal tissues to identify somatic mutations. Further studies will improve our understanding of how ATRX and ERBB4 mutations and AKT/mTOR signaling promote CSCNET tumorigenesis, and may be leveraged in novel anti-cancer treatment strategies.

Genetic factors underlying discordance in chromatin accessibility between monozygotic twins.

BACKGROUND: Open chromatin is implicated in regulatory processes; thus, variations in chromatin structure may contribute to variations in gene expression and other phenotypes. In this work, we perform targeted deep sequencing for open chromatin, and array-based genotyping across the genomes of 72 monozygotic twins to identify genetic factors regulating co-twin discordance in chromatin accessibility. RESULTS: We show that somatic mutations cause chromatin discordance mainly via the disruption of transcription factor binding sites. Structural changes in DNA due to C:G to A:T transversions are under purifying selection due to a strong impact on chromatin accessibility. We show that CpGs whose methylation is specifically regulated during cellular differentiation appear to be protected from high mutation rates of 5'-methylcytosines, suggesting that the spectrum of CpG variations may be shaped fully at the developmental level but not through natural selection. Based on the association mapping of within-pair chromatin differences, we search for cases in which twin siblings with a particular genotype had chromatin discordance at the relevant locus. We identify 1,325 chromatin sites that are differentially accessible, depending on the genotype of a nearby locus, suggesting that epigenetic differences can control regulatory variations via interactions with genetic factors. Poised promoters present high levels of chromatin discordance in association with either somatic mutations or genetic-epigenetic interactions. CONCLUSION: Our observations illustrate how somatic mutations and genetic polymorphisms may contribute to regulatory, and ultimately phenotypic, discordance.

Unraveling human protein interaction networks underlying co-occurrences of diseases and pathological conditions.

BACKGROUND: Human diseases frequently cause complications such as obesity-induced diabetes and share numbers of pathological conditions, such as inflammation, by dysfunctions of common functional modules, such as protein-protein interactions (PPIs). METHODS: Our developed pipeline, ICod (Interaction analysis for disease Comorbidity), grades similarities between pairs of disease-related PPIs including comorbid diseases and pathological conditions. ICod displayed a disease similarity network consisting of nodes of disease PPIs and edges of similarity value. As a proof of concept, eight complex diseases and pathological conditions, such as type 2 diabetes, obesity, inflammation, and cancers, were examined to discover whether PPIs shared between diseases were associated with comorbidities. RESULTS: By comparing Medicare reports of disease co-occurrences from 31 million patients, the disease similarity network shows that PPIs of pathological conditions, including insulin resistance, and inflammation, overlap significantly with PPIs of various comorbid diseases, including diabetes, obesity, and cancers (p < 0.05). Interestingly, maintaining connectivity between essential genes was more drastically perturbed by removing a node of a disease-related gene rather than a pathological condition-related gene, such as one related to inflammations. CONCLUSION: Thus, PPIs of pathological symptoms are underlying functional modules across diseases accompanying comorbidity phenomena, whereas they contribute only marginally to maintaining interactions between essential genes.

Human transcriptome analysis of acute responses to glucose ingestion reveals the role of leukocytes in hyperglycemia-induced inflammation.

Glucose ingestion-induced hyperglycemia has been known to induce inflammation, which is related to the pathogenesis of diabetic complications. To examine acute gene expression responses to physiological oral glucose ingestion in human circulating leukocytes, we conducted a microarray study of human circulating leukocytes sampled before, 1 h after, and 2 h after glucose ingestion in community-based participants without previous histories of diabetes (n = 60). Ingestion of 75 g glucose successfully induced acute hyperglycemia (glucose concentration 91.6 ± 5.3 mg/dl for fasting and 180.7 ± 48.5 mg/dl for 1 h after glucose ingestion). Oral glucose ingestion significantly increased the expressions of 23 genes and decreased the expressions of 13 genes [false discovery rate (FDR) P value <0.05]. These genes are significantly involved in immunity by way of natural killer cell-mediated immunity, granulocyte-mediated immunity, and the cytokine-mediated signaling pathway (FDR P value <0.05). The present study demonstrated 36 genes that showed acute gene expression change in human leukocytes within 1 h after glucose ingestion, suggesting that leukocytes participate in the inflammatory process induced by acute hyperglycemia. We believe that these results will provide some basic insight into the role of leukocytes in hyperglycemia-induced inflammation and the pathogenesis of diabetic complications.

Replication of genome-wide association studies on asthma and allergic diseases in Korean adult population.

Allergic diseases such as asthma, allergic rhinitis, and atopic dermatitis are heterogeneous diseases characterized by multiple symptoms and phenotypes. Recent advancements in genetic study enabled us to identify disease associated genetic factors. Numerous genome-wide association studies (GWAS) have revealed multiple associated loci for allergic diseases. However, the majority of previous studies have been conducted in populations of European ancestry. Moreover, the associations of single nucleotide polymorphisms (SNPs) with allergic diseases have not been studied amongst the large-scale general Korean population. Herein, we performed the replication study to validate the previous variants, known to be associated with allergic diseases, in the Korean population. In this study, we categorized three allergic related phenotypes, one allergy and two asthma related phenotypes, based on self-reports of physician diagnosis and their symptoms from 8,842 samples. As a result, we found nominally significant associations of 6 SNPs with at least one allergic related phenotype in the Korean population.