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Abstract Patients with severe eosinophilic asthma often require systemic medication, including corticosteroids and anti-type 2 (T2) cytokine biologics, to control the disease. While anti-IL5 and anti-IL4Rα antibodies suppress the effects of IL-4, IL-5 and IL-13, the molecular pathways modified by these biologics that are associated with clinical improvement remain unclear. Therefore, we aimed to describe the effects of T2-targeting biologics on the gene expression of blood immune cells. We conducted single-cell RNA sequencing (scRNA-seq) of peripheral blood mononuclear cells (PBMCs) from eight patients with severe eosinophilic asthma treated with mepolizumab, reslizumab, or dupilumab. PBMCs were obtained before the initiation of biologics and at 1- and 6-month timepoints after the initiation of treatment to elucidate treatment-induced changes. During treatment, the proportions of T cells/natural killer (NK) cells, myeloid cells, and B cells did not change. However, the composition of classical monocytes (CMs) changed: IL1B + CMs were reduced, and S100A + CMs were increased. The subsets of T cells also changed, and significant downregulation of the NF-κB pathway was observed. The genes related to the NF-κB pathway were suppressed across T/NK, myeloid, and B cells. The transcriptional landscape did not significantly change after the first month of treatment, but marked changes occurred at six-month intervals. In conclusion, regardless of the type of biologics used, suppression of T2-mediated pathways ultimately reduces the expression of genes related to NF-κB signaling in circulating immune cells. Further studies are warranted to identify potential biomarkers related to treatment response and long-term outcomes. Clinical trial registration number: NCT05164939

Abstract Most previous genome-wide association studies (GWASs) on Parkinson’s disease (PD) focus on the European population. There are several sex-specific clinical differences in PD, but little is known about its genetic background. We aimed to perform an ethnicity-specific and sex-specific GWAS on PD in the Korean population. A total of 1050 PD patients and 5000 controls were included. For primary analysis, we performed a GWAS using a logistic additive model adjusted for age and sex. The same statistical models were applied to sex-specific analyses. Genotyping was performed using a customized microarray chip optimized for the Korean population. Nine single nucleotide polymorphisms (SNPs) including four in the SNCA locus and three from the PARK16 locus were associated with PD in Koreans. The rs34778348 in the LRRK2 locus showed a strong association, though failed to pass cluster quality control. There were no notable genome-wide significant markers near the MAPT or GBA1 loci. In the female-only analysis, rs34778348 in LRRK2 and the four other SNPs in the SNCA showed a strong association with PD. In the male-only analysis, no SNP surpassed the genome-wide significance threshold under Bonferroni correction; however, the most significant signal was rs708726 in the PARK16 locus. This ethnicity- and sex-specific GWAS on PD implicate the pan-ethnic effect of SNCA, the universal but East-Asian inclined effect of PARK16, the East Asian-specific role of LRRK2 G2385R variants, and the possible disproportionate effect of SNCA and PARK16 between sexes for PD susceptibility. These findings suggest the different genetic contributions to sporadic PD in terms of ethnicity and sex.

Background: In previous studies, several asthma phenotypes were identified using clinical and demographic parameters. Transcriptional phenotypes were mainly identified using sputum and bronchial cells. Objective: We aimed to investigate asthma phenotypes via clustering analysis using clinical variables and compare the transcription levels among clusters using gene expression profiling of the blood. Methods: Clustering analysis was performed using 6 parameters: age of asthma onset, body mass index, pack-years of smoking, forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity, and blood eosinophil counts. Peripheral blood mononuclear cells (PBMCs) were isolated from whole blood samples and RNA was extracted from selected PBMCs. Transcriptional profiles were generated (Illumina NovaSeq 6000) and analyzed using the reference genome and gene annotation files (hg19.refGene.gft). Pathway enrichment analysis was conducted using GO, KEGG, and REACTOME databases. Results: In total, 355 patients with asthma were included in the analysis, of whom 72 (20.3%) had severe asthma. Clustering of the 6 parameters revealed 4 distinct subtypes. Cluster 1 (n = 63) had lower predicted FEV1 % and higher pack-years of smoking and neutrophils in sputum. Cluster 2 (n = 43) had a higher proportion and number of eosinophils in sputum and blood, and severe airflow limitation. Cluster 3 (n = 110) consisted of younger subjects with atopic features. Cluster 4 (n = 139) included features of late-onset mild asthma. Differentially expressed genes between clusters 1 and 2 were related to inflammatory responses and cell activation. Th17 cell differentiation and interferon gamma-mediated signaling pathways were related to neutrophilic inflammation in asthma. Conclusion: Four clinical clusters were differentiated based on clinical parameters and blood eosinophils in adult patients with asthma form the Cohort for Reality and Evolution of Adult Asthma in Korea (COREA) cohort. Gene expression profiling and molecular pathways are novel means of classifying asthma phenotypes.

Abstract Background Several genetic variants are known to be associated with nonalcoholic fatty liver disease (NAFLD). We aimed to evaluate the longitudinal associations between genetic variants and NAFLD. Methods We performed a genome-wide association study (GWAS) in Korean individuals who underwent repeated health check-ups. NAFLD was defined by ultrasonography and exclusion of secondary causes. Results The subjects had a median age of 50.0 years, and 54.8% were male. The median follow-up duration was 39 months. Among the 3905 subjects without NAFLD at baseline, 874 (22.4%) subjects developed NAFLD, and among the 1818 subjects with NAFLD at baseline, NAFLD regressed in 336 (18.5%) subjects during the follow-up period. After adjusting for age, sex and body mass index, no single-nucleotide polymorphism (SNP) passed Bonferroni correction for genome-wide significance in the development or regression of NAFLD. Among the SNPs that passed the genome-wide suggestiveness threshold (p = 1E-04) in the discovery set in the GWAS, only 1 SNP (rs4906353) showed an association with the development of NAFLD, with marginal significance in the validation set (p-value, discovery set = 9.68E-5 and validation set = 0.00531). Conclusions This exploratory study suggests that longitudinal changes in NAFLD are not associated with genetic variants in the Korean population. These findings provide new insight into genetic mechanisms in the pathogenesis of NAFLD.

Background and AimThere is a growing evidence that fluctuation in lipid profiles is important in cardiovascular outcomes. We aimed to identify single nucleotide polymorphism (SNP) variants associated with low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) variability in statin-naïve Korean subjects and evaluate their associations with coronary atherosclerosis.MethodsIn statin-naïve subjects from Gene-Environment of Interaction and phenotype cohort, we performed genome-wide association studies of lipid variability; the discovery (first) and replication (second) sets included 4,287 and 1,086 subjects, respectively. Coronary artery calcium (CAC) score and degree of coronary artery stenosis were used as outcome measures. Cholesterol variability was determined by standard deviation and average successive variability, and significant coronary atherosclerosis was defined as CAC score ≥400 or coronary stenosis ≥70%.ResultsMean HDL-C and LDL-C level were 54 ± 12 and 123 ± 30 mg/dL in the first set and 53 ± 12 and 126 ± 29 mg/dL in the second set. APOA5 rs662799 and APOA5 rs2266788 were associated with LDL-C variability and PXDNL rs80056520, ALDH2 rs671, HECTD4 rs2074356, and CETP rs2303790 were SNPs associated for HDL-C variability. APOA5 rs662799 passed Bonferroni correction with p-value of 1.789 × 10−9. Among the SNPs associated with cholesterol variability, rs80056520 and rs2266788 variants were associated with CACS ≥400 and coronary stenosis ≥70% and rs662799 variant was associated with coronary stenosis ≥70%.ConclusionTwo SNPs associated with LDL-C variability (APOA5 rs662799 and rs2266788) and one SNP associated with HDL-C variability (PXDNL rs80056520) were significantly associated with advanced coronary artery stenosis. Combining GWAS results with imaging parameters, our study may provide a deeper understanding of underlying pathogenic basis of the link between lipid variability and coronary atherosclerosis.

Metabolic syndrome (MetS) which is caused by obesity and insulin resistance, is well known for its predictive capability for the risk of type 2 diabetes mellitus and cardiovascular disease. The development of MetS is associated with multiple genetic factors, environmental factors and lifestyle. We performed a genome-wide association study to identify single-nucleotide polymorphism (SNP) related to MetS in large Korean population based samples of 1,362 subjects with MetS and 6,061 controls using the Axiom® Korean Biobank Array 1.0. We replicated the data in another sample including 502 subjects with MetS and 1,751 controls. After adjusting for age and sex, rs662799 located in the APOA5 gene were significantly associated with MetS. 15 SNPs in GCKR, C2orf16, APOA5, ZPR1, and BUD13 were associated with high triglyceride (TG). 14 SNPs in APOA5, ALDH1A2, LIPC, HERPUD1, and CETP, and 2 SNPs in MTNR1B were associated with low high density lipoprotein cholesterol (HDL-C) and high fasting blood glucose respectively. Among these SNPs, 6 TG SNPs: rs1260326, rs1260333, rs1919127, rs964184, rs2075295 and rs1558861 and 11 HDL-C SNPs: rs4775041, rs10468017, rs1800588, rs72786786, rs173539, rs247616, rs247617, rs3764261, rs4783961, rs708272, and rs7499892 were first discovered in Koreans. Additional research is needed to confirm these 17 novel SNPs in Korean population.

BackgroundAlthough genetic features vary across ethnicities, few genome-wide association studies (GWAS) have reported the genetic determinants of liver enzyme expression. This study was aimed to evaluate the associations of genome-wide single nuclear polymorphisms (SNPs) with the liver enzymes in a Korean population.MethodsWe performed a GWAS to identify genetic loci influencing liver function, as measured by concentrations of alkaline phosphatase (ALP), alanine transaminase (ALT), gamma-glutamyl transferase (GGT) and total bilirubin (BIL) in in Korean study participants.ResultsA total of 6,488 subjects (4,457 in the discovery and 2,031 in the validation set) were included. The mean subject age was 50.0±10.6 years (male, 53.7%). Among a total of 546,738 SNPs tested, rs651007 and rs579459 located in the ABO gene showed strong associations with ALP (P = 1.63×10-8 and 5.61×10-8, respectively [discovery set]; P = 4.08×10-15 and 9.92×10-16, respectively [validation set]). Additionally, rs5751901 and rs2006092, which are located in the GGT1 gene, showed strong associations with GGT (P = 6.44×10-15 and 1.26×10-15, respectively [discovery set]; P = 4.13×10-10 and 5.15×10-11, respectively [validation set]). Among the 13 SNPs that showed genome-wide significance with total bilirubin levels, rs10929302 and rs6742078 showed the most significant association (P = 3.08×10-64 and 2.05×10-62, respectively [discovery set]; P = 1.33×10-116 and 2.24×10-118, respectively [validation set]). No genome-wide significant associations was found for ALT.ConclusionsWe demonstrated that ABO, GGT1 and UGT1A family were associated with ALP, GGT and BIL, respectively in Korean population. These findings differ from reported results in GWAS in European populations in terms of associated genes and locations, suggesting different genetic mechanisms of liver enzyme regulation according to ethnicity.

Epidemiologic evidence indicates that the prevalence and severity of coronary artery disease vary depending on ethnicity. In this study, a genome-wide association study for coronary artery calcification (CAC) was performed in a Korean population-based sample of 400 subjects without prior coronary artery disease and replicated in another of 1,288 subjects. CAC score, as assessed by multi-detector computed tomography, was evaluated in volunteers for screening purposes as part of a routine health examination. CAC score greater than the 90th percentile across the age in each sex group was considered severe CAC. Single nucleotide polymorphisms (SNPs) associated with severe CAC after adjusting for age, sex, hypertension, and diabetes were investigated using the additive model of logistic regression. One SNP (rs10757272 in the intronic region of the CDKN2B-AS1 gene in chromosome 9p21.3) met Bonferroni correction in the discovery set (p = 7.55E-08) and was also significant in the validation set by TaqMan assay (p = 0.036). Subjects with rs10757272 were found to have an increased odds ratio (OR) of having severe CAC in multivariate logistic regression analysis after adjusting for age, sex, hypertension, and diabetes (adjusted OR 3.24 and 95% CI 2.11-4.97). In conclusion, SNP rs10757272 in chromosome 9p21.3 was associated with severe CAC based on age and sex in an asymptomatic community-based Korean population. Therefore, it was associated with promotion of coronary artery calcification in subclinical state.

The prevalence of metabolic syndrome (MS) in the nonobese population is not low. However, the identification and risk mitigation of MS are not easy in this population. We aimed to develop an MS prediction model using genetic and clinical factors of nonobese Koreans through machine learning methods. A prediction model for MS was designed for a nonobese population using clinical and genetic polymorphism information with five machine learning algorithms, including naïve Bayes classification (NB). The analysis was performed in two stages (training and test sets). Model A was designed with only clinical information (age, sex, body mass index, smoking status, alcohol consumption status, and exercise status), and for model B, genetic information (for 10 polymorphisms) was added to model A. Of the 7,502 nonobese participants, 647 (8.6%) had MS. In the test set analysis, for the maximum sensitivity criterion, NB showed the highest sensitivity: 0.38 for model A and 0.42 for model B. The specificity of NB was 0.79 for model A and 0.80 for model B. In a comparison of the performances of models A and B by NB, model B (area under the receiver operating characteristic curve [AUC] = 0.69, clinical and genetic information input) showed better performance than model A (AUC = 0.65, clinical information only input). We designed a prediction model for MS in a nonobese population using clinical and genetic information. With this model, we might convince nonobese MS individuals to undergo health checks and adopt behaviors associated with a preventive lifestyle.

Aims Some genetic susceptibility loci for atrial fibrillation (AF) identified by genome-wide association studies (GWAS) in a European database showed ethnic differences in the Asian population. We explored novel AF susceptibility variants for patients with early-onset AF (=60 years old) among Korean patients who underwent AF catheter ablation. Methods and results A genome-wide association study (GWAS) was conducted with 672 cases (=60 years old, Yonsei AF Ablation cohort) and 3700 controls (Korea Genome Epidemiology Study). Association analysis was performed under an additive model of logistic regression, and replication study was conducted with 200 independent cases of Korean AF Network and 1812 controls. Five previously proven genetic loci (1q24/PRRX1, 4q25/PITX2, 10q24/NEURL, 12q24/TBX5, and 16q22/ZFHX3) were validated. Two novel genetic loci associated with early-onset AF were found on chromosomes 1q32.1/PPFIA4 (rs11579055, P = 6.84 × 10-10) and 4q34.1/HAND2 (rs8180252, P = 1.49 × 10-11) and replicated in an additional independent sample of the Korean AF Network. The identified loci implicate candidate genes that encode proteins related to cell-to-cell connection, hypoxic status, or long non-coding RNA. Conclusion Two novel genetic loci for early-onset AF were identified in Korean patients who underwent catheter ablation. One of the novel susceptibility loci on chromosome 4 has strong associations with previously proven gene in a European ancestry database. [ABSTRACT FROM AUTHOR]