• The Korean Journal of Applied Statistics
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• v.25 no.2
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• pp.269-277
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• 2012

In microarray data analysis, recent efforts have focused on the discovery of gene sets from a pathway or functional categories such as Gene Ontology terms(GO terms) rather than on individual gene function for its direct interpretation of genome-wide expression data. We introduce a meta-analysis method that combines $p$-values for changes of each gene in the group. The method measures the significance of overall treatment-induced change in a gene group. An application of the method to a real data demonstrates that it has benefits over other statistical methods such as Fisher's exact test and permutation methods. The method is implemented in a SAS program and it is available on the author's homepage(http://cafe.daum.net/go.analysis).

• Biomolecules & Therapeutics
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• v.22 no.2
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• pp.143-148
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• 2014

Marfan syndrome (MFS) is a dominantly inherited connective tissue disorder caused by mutations in the gene encoding fibrillin-1 (FBN1) and is characterized by aortic dilatation and dissection, which is the primary cause of death in untreated MFS patients. However, disease progression-associated changes in gene expression in the aortic lesions of MFS patients remained unknown. Using a mouse model of MFS, FBN1 hypomorphic mouse (mgR/mgR), we characterized the aortic gene expression profiles during the progression of the MFS. Homozygous mgR mice exhibited MFS-like phenotypic features, such as fragmentation of elastic fibers throughout the vessel wall and were graded into mgR1-4 based on the pathological severity in aortic walls. Comparative gene expression profiling of WT and four mgR mice using microarrays revealed that the changes in the transcriptome were a direct reflection of the severity of aortic pathological features. Gene ontology analysis showed that genes related to oxidation/reduction, myofibril assembly, cytoskeleton organization, and cell adhesion were differentially expressed in the mgR mice. Further analysis of differentially expressed genes identified several candidate genes whose known roles were suggestive of their involvement in the progressive destruction of aorta during MFS. This study is the first genome-wide analysis of the aortic gene expression profiles associated with the progression of MFS. Our findings provide valuable information regarding the molecular pathogenesis during MFS progression and contribute to the development of new biomarkers as well as improved therapeutic strategies.

• ALGAE
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• v.26 no.1
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• pp.21-32
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• 2011

Studies of the red algal genus Bostrychia over the last 15 years have made it a model system for many evolutionary processes within red algal species. The combination of newly developed, or first employed methods, in red algal species studies has made Bostrychia a pioneer genus in intraspecific studies. Bostrychia was the first genus in which a mitochondrial marker was used for intraspecific red algal phylogeny, and the first for which a 3-genome phylogeny was undertaken. The genus was the first red alga used to genetically show maternal plastid and mitochondria inheritance, and also to show correlation between cryptic species (genetically divergent intraspecific lineages) and reproductive incompatibility. The chemotaxonomic use, and physiological function of osmolytes, has also been extensively studied in Bostrychia. Our continuous studies of Bostrychia also highlight important aspects in algal species studies. Our worldwide sampling, and resampling in certain areas, show that intensive sampling is needed to accurately assess the genetic diversity and therefore phylogeographic history of algal species, with increased sampling altering evolutionary hypotheses. Our studies have also shown that long-term morphological character stability (stasis) and character convergence can only be correctly assessed with wide geographic sampling of morphological species. While reproductive incompatibility of divergent lineages supports the biological species nature of these lineages, reproductive incompatibility is also seen between isolates with little genetic divergence. It seems that reproductive incompatibility may evolve quickly in red algae and the unique early stages of fertilization (e.g., gametes covered by walls, active movement of spermatium nuclei to the distant egg nucleus), also well investigated in Bostrychia,. may be key to our understanding of this process.

• Journal of Microbiology and Biotechnology
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• v.30 no.4
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• pp.615-621
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• 2020

Laccases are multicopper oxidases with important industrial value. In the study, a novel laccase gene (mco) in a Staphylococcus haemolyticus isolate is identified and heterologously expressed in Escherichia coli. Mco shares less than 40% of amino acid sequence identities with the other characterized laccases, exhibiting the maximal activity at pH 4.0 and 60℃ with 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) as a substrate. Additionally, the Mco is tolerant to a wide range of pH, heavy metal ions and many organic solvents, and it has a high decolorization capability toward textile dyes in the absence of redox mediators. The characteristics of the Mco make this laccase potentially useful for industrial applications such as textile finishing. Based on BLASTN results, mco is found to be widely distributed in both the bacterial genome and bacterial plasmids. Its potential role in oxidative defense ability of staphylococci may contribute to the bacterial colonization and survival.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.3
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• pp.353-360
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• 2017

Several human diseases have been associated with mitochondrial voltage-dependent anion channel-1 (VDAC1) due to its role in calcium ion transportation and apoptosis. Recent studies suggest that VDAC1 may interact with endothelium-dependent nitric oxide synthase (eNOS). Decreased VDAC1 expression may limit the physical interaction between VDAC1 and eNOS and thus impair nitric oxide production, leading to cardiovascular diseases, including pulmonary arterial hypertension (PAH). In this report, we conducted meta-analysis of genome-wide expression data to identify VDAC1 influenced genes implicated in PAH pathobiology. First, we identified the genes differentially expressed between wild-type and Vdac1 knockout mouse embryonic fibroblasts in hypoxic conditions. These genes were deemed to be influenced by VDAC1 deficiency. Gene ontology analysis indicates that the VDAC1 influenced genes are significantly associated with PAH pathobiology. Second, a molecular signature derived from the VDAC1 influenced genes was developed. We suggest that, VDAC1 has a protective role in PAH and the gene expression signature of VDAC1 influenced genes can be used to i) predict severity of pulmonary hypertension secondary to pulmonary diseases, ii) differentiate idiopathic pulmonary artery hypertension (IPAH) patients from controls, and iii) differentiate IPAH from connective tissue disease associated PAH.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2519-2522
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• 2012

Objective: Data from a recent genome-wide association studiesy of gastric cancer (GC) and oesophageal squamous cell carcinoma in Chinese living in the Taihang Mountains of north-central China suggest that 1q22 and 10q23 are susceptibility-associated regions for GC. However, this has not been confirmed in southern Chinese populations. The aim of this study was to investigate whether these polymorphisms at 1q22 and 10q23 are associated with the risk of GC in a southern Chinese population. Methods: We selected seven top significant associated single nucleotide polymorphisms (SNPs) at 1q22 and 10q23 and conducted a population-based case-control study in a southern Chinese population. Genotypes were determined using MassARRAYTM system (Sequenome, San Diego, CA). Results: Two SNPs at 1q22, rs4072037 and rs4460629, were significantly associated with a reduced risk of GC, best fitting the dominant genetic model. Logistic regression models adjusted for age and sex showed that rs4072037 AG and GG (OR=0.64, P=0.017, compared with AA) and rs4460629 CT and TT (OR=0.54, P=0.0016, compared with TT) significantly reduced the risk of GC. However, no significant results for the five SNPs at 10q23 were obtained in this study. Conclusion: These outcomes indicate that 1q22 is associated with GC susceptibility in this southern Chinese population, while an association for the locus at 10q23 was not confirmed.

• Journal of Korean Neurosurgical Society
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• v.63 no.5
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• pp.559-565
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• 2020

Objective : Conflicting results regarding SOX17 genes and the risk of intracranial aneurysms (IA) exist in the Korean population, although significant positive correlations were noted in genome-wide association studies in European and Japanese populations. Therefore, we aimed to investigate an association between SOX17 gene variants and IA using exome sequencing data. Methods : This study included 26 age-gender matched IA patients and 26 control subjects. The SOX17 gene variants identified from whole-exome sequencing data were examined. Genetic associations to estimate odds ratio (OR) and 95% confidence interval (CI) were performed using the software EPACTS. Results : The mean age of the IA and control groups were 51.0±9.3 years and 49.4±14.3 years, respectively (p=0.623). Seven variants of SOX17, including six single nucleotide polymorphisms and one insertion and deletion, were observed. Among these variants, rs12544958 (A>G) showed the most association with IA, but the association was not statistically significant (OR, 1.97; 95% CI, 0.81-4.74; p=0.125). Minor allele frequencies of the IA patients and controls were 0.788 and 0.653, respectively. None of the remaining variants were significantly associated with IA formation. Conclusion : No significant association between SOX17 gene variants and IA were noted in the Korean population. A large-scale exome sequencing study is necessary to investigate any Korean-specific genetic susceptibility to IA.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9241-9247
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• 2014

Background: Rs31489 in the cleft lip and palate transmembrane1-like gene (CLPTM1L) has been identified to be associated with lung cancer through genome-wide association studies (GWAS). However, some recent replication studies yielded inconclusive results. Thus, we undertook this study to investigate the precise effect of rs31489 on lung cancer susceptibility. Materials and Methods: A hospital-based case-control study in 1,673 Chinese subjects (611 individuals with lung cancer and 1,062 controls) and a meta-analysis among 32,199 subjects (16,364 cases and 15,835 controls) were performed in this study. Results: In our case-control study, rs31489 was inversely associated with lung cancer (AC versus CC: OR=0.68, 95%CI=0.52-0.88; additive model: OR=0.68, 95%CI=0.54-0.85; dominant model: OR=0.65, 95%CI =0.51-0.84). Stratification analysis by smoking status showed a significant association and strong genetic effect in non-smokers but not in smokers. Our meta-analysis further confirmed the association, although with significant heterogeneity contributed by study design and source of controls, as shown by stratified analysis. Sensitive and cumulative analyses both indicated robust stability of our results. In addition, there was no observable publication bias in our meta-analysis. Conclusions: Overall, the findings from our replication study and meta-analysis demonstrated that CLPTM1L gene rs31489 is significantly associated with lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4319-4323
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• 2014

Background: Phospholipase C epsilon 1 (PLCE1) encodes a member of the phospholipase family of proteins that play crucial roles in carcinogenesis and progression of several cancers including esophageal cancer (EC). In two large scale genome-wide association studies (GWAS) single nucleotide polymorphisms (SNP, rs2274223A>G, rs3765524C>T) in PLCE1 were identified as novel susceptibility loci of esophageal cancer (EC) in China. The aim of the present study was to investigate this finding in Kashmir Valley, a high risk area. Materials and Methods: We determined genotypes of three potentially functional SNPs (rs2274223A>G, rs3765524C>T and rs7922612C>T) of PLCE1 in 135 EC patients, and 195 age and gender matched controls in Kashmiri valley by PCR RFLP method. Risk for developing EC was estimated by binary logistic regression using SPSS. Results: The selected PLCE1 polymorphisms did not show independent association with EC. However, the $G_{2274223}T_{3765524}T_{7922612}$ haplotype was significantly associated with increased risk of EC (OR=2.92; 95% CI=1.30-6.54; p=0.009). Smoking and salted tea proved to be independent risk factors for EC. Conclusions: Genetic variations in PLCE1 modulate risk of EC in the high risk Kashmiri population.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3989-3995
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• 2016

Background: Childhood acute lymphoblastic leukemia (ALL) is a heterogeneous genetic disease and its etiology remains poorly understood. Recent genome wide association and replication studies have highlighted specific polymorphisms contributing to childhood ALL predispositions mostly in European populations. It is unclear if these observations generalize to other populations with a lower incidence of ALL. The current case-control study evaluated variants in ARID5B (rs7089424, rs10821936), IKZF1 (rs4132601) and CEBPE (rs2239633) genes, which appear most significantly associated with risk of developing childhood B-lineage ALL. Materials and Methods: Using TaqMan assays, genotyping was conducted for 162 de novo B-lineage ALL cases and 150 unrelated healthy controls in India. Appropriate statistical methods were applied. Results: Genotypic and allelic frequencies differed significantly between cases and controls at IKZF1-rs4132601 (p=0.039, p=0.015) and ARID5B-rs10821936 (p=0.028, p=0.026). Both rs10821936 (p=0.019; OR 0.67; 95% CI=0.47-0.94) and rs4132601 (p=0.018; OR 0.67; 95%CI 0.48-0.94) were associated with reduced disease risk. Moreover, gender-analysis revealed male-specific risk associations for rs10821936 (p=0.041 CT+CC) and rs4132601 (p=0.005 G allele). Further, ARID5B-rs7089424 and CEBPE-rs2239633 showed a trend towards decreased disease risk but without significance (p=0.073; p=0.73). Conclusions: Our findings provide the first evidence that SNPs ARID5B-rs10821936 and IKZF1-rs4132601 are associated with decreased B-lineage ALL susceptibility in Indian children. Understanding the effects of these variants in different ethnic groups is crucial as they may confer different risk of ALL within different populations.