Although genome-wide association studies have identified more than eighty genetic variants associated with non-small cell lung cancer (NSCLC) risk, biological mechanisms of these variants remain largely unknown. By integrating a large-scale genotype data of 15 581 lung adenocarcinoma (AD) cases, 8350 squamous cell carcinoma (SqCC) cases, and 27 355 controls, as well as multiple transcriptome and epigenomic databases, we conducted histology-specific meta-analyses and functional annotations of both reported and novel susceptibility variants. We identified 3064 credible risk variants for NSCLC, which were overrepresented in enhancer-like and promoter-like histone modification peaks as well as DNase I hypersensitive sites. Transcription factor enrichment analysis revealed that USF1 was AD-specific while CREB1 was SqCC-specific. Functional annotation and gene-based analysis implicated 894 target genes, including 274 specifics for AD and 123 for SqCC, which were overrepresented in somatic driver genes (ER = 1.95, P = 0.005). Pathway enrichment analysis and Gene-Set Enrichment Analysis revealed that AD genes were primarily involved in immune-related pathways, while SqCC genes were homologous recombination deficiency related. Our results illustrate the molecular basis of both well-studied and new susceptibility loci of NSCLC, providing not only novel insights into the genetic heterogeneity between AD and SqCC but also a set of plausible gene targets for post-GWAS functional experiments.
Adenocarcinoma of Lung/genetics* ; Carcinoma, Non-Small-Cell Lung/genetics* ; Carcinoma, Squamous Cell/genetics* ; Genetic Heterogeneity ; Genetic Predisposition to Disease ; Genome-Wide Association Study ; Humans ; Lung Neoplasms/genetics* ; Polymorphism, Single Nucleotide

No abstract available.
Genetic Heterogeneity ; Growth Hormone ; Noonan Syndrome

No abstract available.
Genetic Heterogeneity ; Mucocutaneous Lymph Node Syndrome

BACKGROUND AND OBJECTIVES: Patients with Kawasaki disease (KD) are clinically heterogeneous because its diagnosis is based solely on clinical observation and there are no definitive biomarkers. We dissected the clinical heterogeneity of KD patients using the KD-associated genetic variants. METHODS: We performed a genetic association analysis in several KD subgroups categorized by clinical characteristics using the KD-associated variants of the B lymphoid tyrosine kinase (BLK; rs6993775) and Fc gamma receptor II a (FCGR2A; rs1801274) in a large number of case (n=1,011) and control (n=4,533) samples. RESULTS: BLK and FCGR2A were very significantly associated with KD in Korean KD patients (odds ratio [OR],1.48; p=4.63×10⁻¹¹ for BLK, and OR, 1.26; p=1.42×10⁻⁴ for FCGR2A). However, in KD subgroup analysis, we found that neither BLK nor FCGR2A were associated with either incomplete Kawasaki disease (iKD) type patients or those older than 5 years of age (p>0.2), suggesting that patients with iKD or those older than 5 years of age are a unique subgroup of KD. In genetic association analysis after excluding iKD patients and those older than 5 years old, we found that BLK was associated with all KD subgroups, whereas FCGR2A was specifically associated with male KD patients younger than 1 year of age (OR, 2.22; p=2.35×10⁻⁵). CONCLUSIONS: KD is a clinically and genetically heterogeneous disease. These findings will provide new insights into the clinical and genetic heterogeneity of KD.
Biomarkers ; Diagnosis ; Genetic Heterogeneity ; Genome-Wide Association Study ; Humans ; Male ; Mucocutaneous Lymph Node Syndrome ; Polymorphism, Single Nucleotide ; Population Characteristics ; Protein-Tyrosine Kinases

DNA methylation is an important epigenetic mark that plays a vital role in gene expression and cell differentiation. The average DNA methylation level among a group of cells has been extensively documented. However, the cell-to-cell heterogeneity in DNA methylation, which reflects the differentiation of epigenetic status among cells, remains less investigated. Here we established a gold standard of the cell-to-cell heterogeneity in DNA methylation based on single-cell bisulfite sequencing (BS-seq) data. With that, we optimized a computational pipeline for estimating the heterogeneity in DNA methylation from bulk BS-seq data. We further built HeteroMeth, a database for searching, browsing, visualizing, and downloading the data for heterogeneity in DNA methylation for a total of 141 samples in humans, mice, Arabidopsis, and rice. Three genes are used as examples to illustrate the power of HeteroMeth in the identification of unique features in DNA methylation. The optimization of the computational strategy and the construction of the database in this study complement the recent experimental attempts on single-cell DNA methylomes and will facilitate the understanding of epigenetic mechanisms underlying cell differentiation and embryonic development. HeteroMeth is publicly available at http://qianlab.genetics.ac.cn/HeteroMeth.
Animals ; Arabidopsis ; genetics ; Cell Line ; Computer Simulation ; DNA Methylation ; genetics ; Databases, Genetic ; Entropy ; Genetic Heterogeneity ; Genome ; High-Throughput Nucleotide Sequencing ; Humans ; Mice ; Oryza ; genetics ; Reference Standards ; Reproducibility of Results ; Sequence Analysis, DNA ; Single-Cell Analysis ; User-Computer Interface

Clinical and genetic heterogeneity in association with overlapping spectrum is characteristic in pediatric neuromuscular disorders, which makes confirmative diagnosis difficult and time consuming. Considering evolution of molecular genetic diagnosis and resultant upcoming genetically modifiable therapeutic options, rapid and cost-effective genetic testing should be applied in conjunction with existing diagnostic methods of clinical examinations, laboratory tests, electrophysiologic studies and pathologic studies. Earlier correct diagnosis would enable better clinical management for these patients in addition to new genetic drug options and genetic counseling.
Diagnosis ; Genetic Counseling ; Genetic Heterogeneity ; Genetic Testing ; Humans ; Molecular Biology ; Molecular Diagnostic Techniques ; Neuromuscular Diseases ; Pediatrics ; Phenotype

BACKGROUND AND PURPOSE: Paroxysmal dyskinesia is a genetically and clinically heterogeneous movement disorder. Recent studies have shown that it exhibits both phenotype and genotype overlap with other paroxysmal disorders as well as clinical heterogeneity. We investigated the clinical and genetic characteristics of paroxysmal dyskinesia in children. METHODS: Fifty-five patients (16 from 14 families and 39 sporadic cases) were enrolled. We classified them into three phenotypes: paroxysmal kinesigenic dyskinesia (PKD), paroxysmal nonkinesigenic dyskinesia (PNKD), and paroxysmal exercise-induced dyskinesia (PED). We sequenced PRRT2, SLC2A1, and MR-1 in these patients and reviewed their medical records. RESULTS: Forty patients were categorized as PKD, 14 as PNKD, and 1 as PED. Thirty-eight (69.1%) patients were male, and their age at onset was 8.80±4.53 years (mean±SD). Dystonia was the most common symptom (38 patients, 69.1%). Pathogenic variants were identified in 20 patients (36.4%): 18 with PRRT2 and 2 with SLC2A1. All of the patients with PRRT2 mutations presented with PKD alone. The 2 patients carrying SLC2A1 mutations presented as PNKD and PED, and one of them was treated effectively with a ketogenic diet. Six mutations in PRRT2 (including 2 novel variants) were identified in 9 of the 13 tested families (69.2%) and in 8 patients of the 25 tested sporadic cases (32.0%). There were no significant differences in clinical features or drug response between the PRRT2-positive and PRRT2-negative PKD groups. CONCLUSIONS: This study has summarized the clinical and genetic heterogeneity of paroxysmal dyskinesia in children. We suggest that pediatric paroxysmal dyskinesia should not be diagnosed using clinical features alone, but by combining them with broader genetic testing.
Age of Onset ; Child* ; Chorea* ; Dyskinesias ; Dystonia ; Genetic Heterogeneity ; Genetic Testing ; Genotype ; Humans ; Ketogenic Diet ; Male ; Medical Records ; Movement Disorders ; Phenotype ; Population Characteristics

PURPOSE: Melanoma is a highly heterogeneous neoplasm, composed of subpopulations of tumor cells with distinct molecular and biological phenotypes and genotypes. In this study, to determine the genetic heterogeneity between primary and metastatic melanoma in Korean melanoma patients, we evaluated several well-known genetic alterations of melanoma. In addition, to elucidate the clinical relevance of each genetic alteration and heterogeneity between primary and metastatic lesions, clinical features and patient outcome were collected. MATERIALS AND METHODS: In addition to clinical data, BRAF, NRAS, GNAQ/11 mutation and KIT amplification data was acquired from an archived primary Korean melanoma cohort (KMC) of 188 patients. Among these patients, 43 patients were included for investigation of tumor heterogeneity between primary melanoma and its corresponding metastatic lesions. RESULTS: Overall incidence of genetic aberrations of the primary melanomas in KMC was 17.6% of BRAF V600, 12.6% of NRAS mutation, and 28.6% of KIT amplification. GNAQ/11 mutation was seen in 66.6% of the uveal melanoma patients. Patients with BRAF mutation were associated with advanced stage and correlated to poor prognosis (p < 0.01). Among 43 patients, 55.8% showed heterogeneity between primary and metastatic lesion. The frequency of BRAF mutation and KIT amplification significantly increased in the metastatic lesions compared to primary melanomas. GNAQ/11 mutation showed 100% homogeneity in uveal melanoma patients. CONCLUSION: Our data demonstrated heterogeneity between primary melanomas and corresponding metastatic lesions for BRAF, NRAS mutation and KIT amplification. However, GNAQ/11 mutation was genetically homogeneous between primary and metastatic melanoma lesions in uveal melanoma.
Cohort Studies ; Genetic Heterogeneity ; Genotype ; Humans ; Incidence ; Melanoma* ; Phenotype ; Population Characteristics* ; Prognosis

Novel H5N6 highly pathogenic avian influenza viruses (HPAIVs) were isolated from duck farms and migratory bird habitats in South Korea in November to December 2017. Genetic analysis demonstrated that at least two genotypes of H5N6 were generated through reassortment between clade 2.3.4.4 H5N8 HPAIVs and Eurasian low pathogenic avian influenza virus in migratory birds in late 2017, suggesting frequent reassortment of clade 2.3.4.4 H5 HPAIVs and highlighting the need for systematic surveillance in Eurasian breeding grounds.
Agriculture ; Animals ; Birds ; Breeding ; Ducks ; Ecosystem ; Genetic Heterogeneity ; Genotype ; Influenza in Birds ; Korea

Asthma is traditionally regarded as a chronic airway disease, and recent literature proves its heterogeneity, based on distinctive clusters or phenotypes of asthma. In defining such asthma clusters, the nature of comorbidity among patients with asthma is poorly understood, by assuming no causal relationship between asthma and other comorbid conditions, including both communicable and noncommunicable diseases. However, emerging evidence suggests that the status of asthma significantly affects the increased susceptibility of the patient to both communicable and noncommunicable diseases. Specifically, the impact of asthma on susceptibility to noncommunicable diseases such as chronic systemic inflammatory diseases (e.g., rheumatoid arthritis), may provide an important insight into asthma as a disease with systemic inflammatory features, a conceptual understanding between asthma and asthma-related comorbidity, and the potential implications on the therapeutic and preventive interventions for patients with asthma. This review discusses the currently under-recognized clinical and immunological phenotypes of asthma; specifically, a higher risk of developing a systemic inflammatory disease such as rheumatoid arthritis and their implications, on the conceptual understanding and management of asthma. Our discussion is divided into three parts: literature summary on the relationship between asthma and the risk of rheumatoid arthritis; potential mechanisms underlying the association; and implications on asthma management and research.
Arthritis, Rheumatoid* ; Asthma* ; Comorbidity ; Epidemiology ; Genetic Heterogeneity ; Humans ; Phenotype* ; Population Characteristics*