Displaying publications 541 - 560 of 951 in total

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  1. Fulltext Role of mitochondrial DNA mutations in brain tumors: A mini-review
    Mohamed Yusoff AA
    J Cancer Res Ther, 2015 Jul-Sep;11(3):535-44.
    PMID: 26458578 DOI: 10.4103/0973-1482.161925
    Brain tumor is molecularly a heterogeneous group of diseases, and genetic factors seem to play a crucial role in its genesis. Even though multiple alterations in the nuclear-encoded genes such as tumor suppressor and oncogenes are believed to play a key role in brain tumorigenesis, the involvement of the mitochondrial genome to this event remains controversial to date. Mitochondrial DNA (mtDNA) has been suspected to be associated with the carcinogenesis because of its high sensitivity to mutations and inefficient repair mechanisms in comparison to nuclear DNA. Thus, defects in mtDNA could also lead to the development of brain tumor. By virtue of their clonal nature and high copy number, mtDNA mutations may provide a new effective molecular biomarker for the cancer detection. It has been suggested that establishing mtDNA defective pattern might be useful in cancer diagnostics and detection, the prognosis of cancer outcome, and/or the response to certain treatments. This mini-review gives a brief overview on the several aspects of mtDNA, with a particular focus on its role in tumorigenesis and progression of brain tumor. Understanding the role of mitochondria and brain tumor development could potentially translate into therapeutic strategies for patients with these tumors.
    Matched MeSH terms: Genome, Mitochondrial
  2. Fulltext Genome-wide association study of prostate cancer-specific survival
    Szulkin R, Karlsson R, Whitington T, Aly M, Gronberg H, Eeles RA, et al.
    Cancer Epidemiol Biomarkers Prev, 2015 Nov;24(11):1796-800.
    PMID: 26307654 DOI: 10.1158/1055-9965.EPI-15-0543
    BACKGROUND: Unnecessary intervention and overtreatment of indolent disease are common challenges in clinical management of prostate cancer. Improved tools to distinguish lethal from indolent disease are critical.

    METHODS: We performed a genome-wide survival analysis of cause-specific death in 24,023 prostate cancer patients (3,513 disease-specific deaths) from the PRACTICAL and BPC3 consortia. Top findings were assessed for replication in a Norwegian cohort (CONOR).

    RESULTS: We observed no significant association between genetic variants and prostate cancer survival.

    CONCLUSIONS: Common genetic variants with large impact on prostate cancer survival were not observed in this study.

    IMPACT: Future studies should be designed for identification of rare variants with large effect sizes or common variants with small effect sizes.

    Matched MeSH terms: Genome-Wide Association Study
  3. Fulltext Polygenic risk scores for prediction of breast cancer in Korean women
    Jee YH, Ho WK, Park S, Easton DF, Teo SH, Jung KJ, et al.
    Int J Epidemiol, 2023 Jun 06;52(3):796-805.
    PMID: 36343017 DOI: 10.1093/ije/dyac206
    BACKGROUND: Polygenic risk scores (PRSs) for breast cancer, developed using European and Asian genome-wide association studies (GWAS), have been shown to have good discrimination in Asian women. However, prospective calibration of absolute risk prediction models, based on a PRS or PRS combined with lifestyle, clinical and environmental factors, in Asian women is limited.

    METHODS: We consider several PRSs trained using European and/or Asian GWAS. For each PRS, we evaluate the discrimination and calibration of three absolute risk models among 41 031 women from the Korean Cancer Prevention Study (KCPS)-II Biobank: (i) a model using incidence, mortality and risk factor distributions (reference inputs) among US women and European relative risks; (ii) a recalibrated model, using Korean reference but European relative risks; and (iii) a fully Korean-based model using Korean reference and relative risk estimates from KCPS.

    RESULTS: All Asian and European PRS improved discrimination over lifestyle, clinical and environmental (Qx) factors in Korean women. US-based absolute risk models overestimated the risks for women aged ≥50 years, and this overestimation was larger for models that only included PRS (expected-to-observed ratio E/O = 1.2 for women <50, E/O = 2.7 for women ≥50). Recalibrated and Korean-based risk models had better calibration in the large, although the risk in the highest decile was consistently overestimated. Absolute risk projections suggest that risk-reducing lifestyle changes would lead to larger absolute risk reductions among women at higher PRS.

    CONCLUSIONS: Absolute risk models incorporating PRS trained in European and Asian GWAS and population-appropriate average age-specific incidences may be useful for risk-stratified interventions in Korean women.

    Matched MeSH terms: Genome-Wide Association Study
  4. Surveillance, isolation and genomic characterization of Pteropine orthoreovirus of probable bat origin among patients with acute respiratory infection in Malaysia
    Tee KK, Chan PQ, Loh AM, Singh S, Teo CH, Iyadorai T, et al.
    J Med Virol, 2023 Feb;95(2):e28520.
    PMID: 36691929 DOI: 10.1002/jmv.28520
    Pteropine orthoreovirus (PRV), an emerging bat-borne virus, has been linked to cases of acute respiratory infections (ARI) in humans. The prevalence, epidemiology and genomic diversity of PRV among ARI of unknown origin were studied. Among 632 urban outpatients tested negative for all known respiratory viruses, 2.2% were PRV-positive. Patients mainly presented with moderate to severe forms of cough, sore throat and muscle ache, but rarely with fever. Phylogenetic analysis revealed that over 90% of patients infected with the Melaka virus (MelV)-like PRV, while one patient infected with the Pulau virus previously found only in fruit bats. Human oral keratinocytes and nasopharyngeal epithelial cells were susceptible to clinical isolates of PRV, including the newly isolated MelV-like 12MYKLU1034. Whole genome sequence of 12MYKLU1034 using Nanopore technique revealed a novel reassortant strain. Evolutionary analysis of the global PRV strains suggests the continuous evolution of PRV through genetic reassortment among PRV strains circulating in human, bats and non-human primate hosts, creating a spectrum of reassortant lineages with complex evolutionary characteristics. In summary, the role of PRV as a common etiologic agent of ARI is evident. Continuous monitoring of PRV prevalence, pathogenicity and diversity among human and animal hosts is important to trace the emergence of novel reassortants.
    Matched MeSH terms: Genome, Viral
  5. Fulltext Hybridization and reticulate evolution in Diphasiastrum (flat-branched clubmosses, Lycopodiaceae) - New data from the island of Taiwan and Vietnam
    Schnittler M, Inoue M, Shchepin ON, Fuchs J, Chang H, Lamkowski P, et al.
    Mol Phylogenet Evol, 2024 Jul;196:108067.
    PMID: 38561082 DOI: 10.1016/j.ympev.2024.108067
    In the species groups related to Diphasiastrum multispicatum and D. veitchii, hybridization was investigated in samples from northern and southern Vietnam and the island of Taiwan, including available herbarium specimens from southeast Asia. The accessions were analyzed using flow cytometry (living material only), Sanger sequencing and multiplexed inter-simple sequence repeat genotyping by sequencing. We detected two cases of ancient hybridization involving different combinations of parental species; both led via subsequent duplication to tetraploid taxa. A cross D. multispicatum × D. veitchii from Malaysia represents D. wightianum, a tetraploid taxon according to reported DNA content measurements of dried material (genome formulas MM, VV and MMVV, respectively). The second case involves D. veitchii and an unknown diploid parent (genome formula XX). Three hybridogenous taxa (genome formulas VVX, VVXX, VVVX) were discernable by a combination of flow cytometry and molecular data. Taxon I (VVX, three clones found on Taiwan island) is apparently triploid. Taxon II represents another genetically diverse and sexual tetraploid species (VVXX) and can be assigned to D. yueshanense, described from Taiwan island but occurring as well in mainland China and Vietnam. Taxon III is as well most likely tetraploid (VVVX) and represented by at least one, more likely two, clones from Taiwan island. Taxa I and III are presumably asexual and new to science. Two independently inherited nuclear markers recombine only within, not between these hybrids, pointing towards reproductive isolation. We present an evolutionary scheme which explains the origin of the hybrids and the evolution of new and fully sexual species by hybridization and subsequent allopolyploidization in flat-branched clubmosses.
    Matched MeSH terms: Genome, Plant
  6. Exploring the transcription start sites and other genomic features facilitates the accurate identification and annotation of small RNAs across multiple stress conditions in Mycobacterium tuberculosis
    Cheah HL, Citartan M, Lee LP, Ahmed SA, Salleh MZ, Teh LK, et al.
    Funct Integr Genomics, 2024 Sep 12;24(5):160.
    PMID: 39264475 DOI: 10.1007/s10142-024-01437-5
    Mycobacterium tuberculosis (MTB) is a pathogen that is known for its ability to persist in harsh environments and cause chronic infections. Understanding the regulatory networks of MTB is crucial for developing effective treatments. Small regulatory RNAs (sRNAs) play important roles in gene expression regulation in all kingdoms of life, and their classification based solely on genomic location can be imprecise due to the computational-based prediction of protein-coding genes in bacteria, which often neglects segments of mRNA such as 5'UTRs, 3'UTRs, and intercistronic regions of operons. To address this issue, our study simultaneously discovered genomic features such as TSSs, UTRs, and operons together with sRNAs in the M. tuberculosis H37Rv strain (ATCC 27294) across multiple stress conditions. Our analysis identified 1,376 sRNA candidates and 8,173 TSSs in MTB, providing valuable insights into its complex regulatory landscape. TSS mapping enabled us to classify these sRNAs into more specific categories, including promoter-associated sRNAs, 5'UTR-derived sRNAs, 3'UTR-derived sRNAs, true intergenic sRNAs, and antisense sRNAs. Three of these sRNA candidates were experimentally validated using 3'-RACE-PCR: predictedRNA_0240, predictedRNA_0325, and predictedRNA_0578. Future characterization and validation are necessary to fully elucidate the functions and roles of these sRNAs in MTB. Our study is the first to simultaneously unravel TSSs and sRNAs in MTB and demonstrate that the identification of other genomic features, such as TSSs, UTRs, and operons, allows for more accurate and specific classification of sRNAs.
    Matched MeSH terms: Genome, Bacterial
  7. Fulltext Emergence of SARS-CoV-2 omicron variant JN.1 in Tamil Nadu, India - Clinical characteristics and novel mutations
    Selvavinayagam ST, Sankar S, Yong YK, Murugesan A, Suvaithenamudhan S, Hemashree K, et al.
    Sci Rep, 2024 Jul 30;14(1):17476.
    PMID: 39080396 DOI: 10.1038/s41598-024-68678-z
    In December 2023, we observed a notable shift in the COVID-19 landscape, when JN.1 omicron emerged as the predominant SARS-CoV-2 variant with a 95% incidence. We characterized the clinical profile, and genetic changes in JN.1, an emerging SARS-CoV-2 variant of interest. Whole genome sequencing was performed on SARS-CoV-2 positive clinical specimens, followed by sequence analysis. Mutations within the spike protein sequences were analysed and compared with the previously reported lineages and sub-lineages, to identify the potential impact of the unique mutations on protein structure and possible alterations in the functionality. Several unique and dynamic mutations were identified herein. Molecular docking analysis showed changes in the binding affinity, and key interacting residues of wild-type and mutated structures with key host cell receptors of SARS-CoV-2 entry viz., ACE2, CD147, CD209L and AXL. Our data provides key insights on the emergence of newer variants and highlights the necessity for robust and sustained global genomic surveillance of SARS-CoV-2.
    Matched MeSH terms: Genome, Viral
  8. Fulltext Genetic Signatures of Positive Selection in Human Populations Adapted to High Altitude in Papua New Guinea
    González-Buenfil R, Vieyra-Sánchez S, Quinto-Cortés CD, Oppenheimer SJ, Pomat W, Laman M, et al.
    Genome Biol Evol, 2024 Aug 05;16(8).
    PMID: 39173139 DOI: 10.1093/gbe/evae161
    Papua New Guinea (PNG) hosts distinct environments mainly represented by the ecoregions of the Highlands and Lowlands that display increased altitude and a predominance of pathogens, respectively. Since its initial peopling approximately 50,000 years ago, inhabitants of these ecoregions might have differentially adapted to the environmental pressures exerted by each of them. However, the genetic basis of adaptation in populations from these areas remains understudied. Here, we investigated signals of positive selection in 62 highlanders and 43 lowlanders across 14 locations in the main island of PNG using whole-genome genotype data from the Oceanian Genome Variation Project (OGVP) and searched for signals of positive selection through population differentiation and haplotype-based selection scans. Additionally, we performed archaic ancestry estimation to detect selection signals in highlanders within introgressed regions of the genome. Among highland populations we identified candidate genes representing known biomarkers for mountain sickness (SAA4, SAA1, PRDX1, LDHA) as well as candidate genes of the Notch signaling pathway (PSEN1, NUMB, RBPJ, MAML3), a novel proposed pathway for high altitude adaptation in multiple organisms. We also identified candidate genes involved in oxidative stress, inflammation, and angiogenesis, processes inducible by hypoxia, as well as in components of the eye lens and the immune response. In contrast, candidate genes in the lowlands are mainly related to the immune response (HLA-DQB1, HLA-DQA2, TAAR6, TAAR9, TAAR8, RNASE4, RNASE6, ANG). Moreover, we find two candidate regions to be also enriched with archaic introgressed segments, suggesting that archaic admixture has played a role in the local adaptation of PNG populations.
    Matched MeSH terms: Genome, Human
  9. Accelerating crop improvement via integration of transcriptome-based network biology and genome editing
    Razalli II, Abdullah-Zawawi MR, Tamizi AA, Harun S, Zainal-Abidin RA, Jalal MIA, et al.
    Planta, 2025 Mar 17;261(4):92.
    PMID: 40095140 DOI: 10.1007/s00425-025-04666-5
    Big data and network biology infer functional coupling between genes. In combination with machine learning, network biology can dramatically accelerate the pace of gene discovery using modern transcriptomics approaches and be validated via genome editing technology for improving crops to stresses. Unlike other living things, plants are sessile and frequently face various environmental challenges due to climate change. The cumulative effects of combined stresses can significantly influence both plant growth and yields. In navigating the complexities of climate change, ensuring the nourishment of our growing population hinges on implementing precise agricultural systems. Conventional breeding methods have been commonly employed; however, their efficacy has been impeded by limitations in terms of time, cost, and infrastructure. Cutting-edge tools focussing on big data are being championed to usher in a new era in stress biology, aiming to cultivate crops that exhibit enhanced resilience to multifactorial stresses. Transcriptomics, combined with network biology and machine learning, is proving to be a powerful approach for identifying potential genes to target for gene editing, specifically to enhance stress tolerance. The integration of transcriptomic data with genome editing can yield significant benefits, such as gaining insights into gene function by modifying or manipulating of specific genes in the target plant. This review provides valuable insights into the use of transcriptomics platforms and the application of biological network analysis and machine learning in the discovery of novel genes, thereby enhancing the understanding of plant responses to combined or sequential stress. The transcriptomics as a forefront omics platform and how it is employed through biological networks and machine learning that lead to novel gene discoveries for producing multi-stress-tolerant crops, limitations, and future directions have also been discussed.
    Matched MeSH terms: Genome, Plant
  10. Fulltext Genomic epidemiology of Plasmodium knowlesi reveals putative genetic drivers of adaptation in Malaysia
    Westaway JAF, Diez Benavente E, Auburn S, Kucharski M, Aranciaga N, Nayak S, et al.
    PLoS Negl Trop Dis, 2025 Mar;19(3):e0012885.
    PMID: 40072967 DOI: 10.1371/journal.pntd.0012885
    Sabah, Malaysia, has amongst the highest burden of human Plasmodium knowlesi infection in the world, associated with increasing encroachment on the parasite's macaque host habitat. However, the genomic make-up of P. knowlesi in Sabah was previously poorly understood. To inform on local patterns of transmission and putative adaptive drivers, we conduct population-level genetic analyses of P. knowlesi human infections using 52 new whole genomes from Sabah, Malaysia, in combination with publicly available data. We identify the emergence of distinct geographical subpopulations within the macaque-associated clusters using identity-by-descent-based connectivity analysis. Secondly, we report on introgression events between the clusters, which may be linked to differentiation of the subpopulations, and that overlap genes critical for survival in human and mosquito hosts. Using village-level locations from P. knowlesi infections, we also identify associations between several introgressed regions and both intact forest perimeter-area ratio and mosquito vector habitat suitability. Our findings provide further evidence of the complex role of changing ecosystems and sympatric macaque hosts in Malaysia driving distinct genetic changes seen in P. knowlesi populations. Future expanded analyses of evolving P. knowlesi genetics and environmental drivers of transmission will be important to guide public health surveillance and control strategies.
    Matched MeSH terms: Genome, Protozoan
  11. Whole-genome sequencing of extended spectrum beta lactamases (ESBLs)-producing Klebsiella pneumoniae (kp) isolates from selected hospitals in Malaysia
    Adamu S, Ali MB, Desa MNM, Neoh HM, Masri SN, Joseph N, et al.
    BMC Genomics, 2025 Mar 31;26(1):322.
    PMID: 40165075 DOI: 10.1186/s12864-025-11215-7
    The resistance of ESBLs-producing Kp to various groups of antibiotics commonly used against infections they caused had become a global threat and required urgent attention. This study assessed the extended spectrum beta-lactamases (ESBLs)-producing Klebsiella pneumoniae isolates in terms of their genomic resistance. An analytical profile index (API) 20E kit was used to confirm a total of 100 clinical isolates of ESBL Klebsiella pneumoniae. The disc diffusion method was used to perform the antimicrobial susceptibility testing (AST), which was followed by the phenotypic detection of ESBLs. Six profiled representative ESBL positive strains were subjected to whole genome sequencing (WGS), multilocus sequence typing (MLST), and phylogenetic tree construction using the sequence data. The study showed that 46(46%) of the 100 isolates were positive for ESBL production and antibiotic susceptibility testing revealed significant resistance to β-lactam antibiotics including monobactam especially ampicillin/sulbactam (40%), cephalosporin groups (cefuroxime, cefotaxime, and ceftriaxone) stood at 51%, 49% and 48% respectively and aztreonam with 49%. The WGS analysis of the representative strains revealed genes encoding resistance to aminoglycoside (StrA4, StrB1, aac(3')-IIa, aac(6')-1b, aac(6')1b-cr-1, aadA16, aph(3')-VIa and aadA15), trimethoprim (dfrA14 and dfrA27), sulphonamide (sul1_11, sul2_2 and sul2_3), quinolone (QnrB40-1, QnrB10, QnrS2, OqxA and OqxB), tetracycline (tet(A)_4), fosfomycin (fosA3, floR2 and fosA7), macrolid (mph(A)_1), rifampicin (ARR-3), β-lactam (blaCTX-M-15_23, blaCTX-M-55, blaSHV-1_22, blaSHV11_18, blaSHV-11, blaSHV-1_1.1, blaSHV-11_3, blaSHV-11_19, blaTEM-1_1, blaTEM-1_5, blaOXA-51_10, blaOXA-30_1, blaNDM-1, blaLEN6, blaLEN8 and blaLEN21 were detected. The MLST analysis revealed two novel sequence types of representative strains (2 with ST NF* and 12 with ST NF) and four other heterogeneous STs which include ST394, ST985, ST17 and ST11 while the phylogenetic tree of the strains showed closed clonal relationship and lineages with other reference isolates. In conclusion, the study's results showed a high prevalence of ESBL-producing Kp in the study area, and the representative strains' genomic contents demonstrated that ESBL-producing Kp in a clinical setting could serve as a reservoir for resistance genes and be the source of genetic transfer to other bacterial species. As a result, ongoing surveillance is required to monitor this endemic situation to prevent an epidemiological outbreak of K. pneumoniae- carrying ESBL.
    Matched MeSH terms: Genome, Bacterial
  12. Genome-Guided Identification and Characterisation of Broad-Spectrum Antimicrobial Compounds of Bacillus velezensis Strain PD9 Isolated from Stingless Bee Propolis
    Puan SL, Erriah P, Yahaya NM, Ali MSM, Ahmad SA, Oslan SN, et al.
    Probiotics Antimicrob Proteins, 2025 Dec;17(6):5042-5065.
    PMID: 39815115 DOI: 10.1007/s12602-025-10451-3
    The emergence of multidrug-resistant pathogens presents a significant global health challenge, which is primarily fuelled by overuse and misuse of antibiotics. Bacteria-derived antimicrobial metabolites offer a promising alternative strategy for combating antimicrobial resistance issues. Bacillus velezensis PD9 (BvPD9), isolated from stingless bee propolis, has been reported to have antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA). This study aimed to characterise and identify the antimicrobial compounds (AMCs) synthesised by BvPD9 through integration of genome mining and liquid chromatography-mass spectrometry (LC-MS) analysis. The whole-genome sequence of BvPD9 contained 4,263,351 base pairs and 4101 protein-coding sequences, with 12 potential AMC biosynthetic gene clusters. Comparative genomic analysis highlighted the unique profile of BvPD9 that possesses the largest number of unknown proteins, indicating significant potential for further exploration. The combined genomics-metabolic profiling uncovered five AMCs in BvPD9 extract, including bacillibactin, bacilysin, surfactin A, fengycin A, and bacillomycin D. The extract exhibited a broad antibacterial spectrum against 25 pathogenic bacteria, including both Gram-positive and Gram-negative bacteria, with the lowest minimum inhibitory concentration (MIC, 0.032 mg/ml) against S. epidermidis ATCC 12228, and the lowest minimum bactericidal concentration (MBC; 0.128 mg/ml) against MRSA ATCC 700699 and Aeromonas hydrophilia. The robust stability of BvPD9 extract was demonstrated at high temperatures, over a wide range of pH conditions (6 to 12) and in the presence of various hydrolytic enzymes. Additionally, the extract showed 50% haemolytic and cytotoxicity activity at 0.158 and 0.250 mg/ml, respectively. These characteristics suggest potential applications of BvPD9 metabolites for tackling antimicrobial resistance and its applicability across diverse industries.
    Matched MeSH terms: Genome, Bacterial
  13. Next generation sequencing yields the complete mitochondrial genome of the Clarion angelfish, Holacanthus clarionensis (Perciformes: Pomacanthidae)
    Shen KN, Chang CW, Loh KH, Chen CH, Hsiao CD
    Mitochondrial DNA A DNA Mapp Seq Anal, 2016 11;27(6):4118-4119.
    PMID: 25600747
    In this study, the complete mitogenome sequence of the Clarion angelfish, Holacanthus clarionensis (Perciformes: Pomacanthidae) has been sequenced by next-generation sequencing method. The length of the assembled mitogenome is 16,615 bp, including 13 protein coding genes, 22 transfer RNAs, and two ribosomal RNAs genes. The overall base composition of Clarion angelfish is 28.3% for A, 29.3% for C, 16.5% for G, 25.9% for T and show 85% identities to flame angelfish Centropyge loriculus. The complete mitogenome of the Clarion angelfish provides essential and important DNA molecular data for further phylogeography and evolutionary analysis for marine angelfish phylogeny.
    Matched MeSH terms: Genome, Mitochondrial/genetics*
  14. An updated review of avian-origin Tembusu virus: a newly emerging avian Flavivirus
    Zhang W, Chen S, Mahalingam S, Wang M, Cheng A
    J Gen Virol, 2017 Oct;98(10):2413-2420.
    PMID: 28874226 DOI: 10.1099/jgv.0.000908
    Tembusu virus (TMUV, genus Flavivirus, family Flaviviridae) was first isolated in 1955 from Culex tritaeniorhynchus mosquitoes in Kuala Lumpur, Malaysia. In April 2010, duck TMUV was first identified as the causative agent of egg-drop syndrome, characterized by a substantial decrease in egg laying and depression, growth retardation and neurological signs or death in infected egg-laying and breeder ducks, in the People's Republic of China. Since 2010, duck TMUV has spread to most of the duck-producing regions in China, including many of the coastal provinces, neighbouring regions and certain Southeast Asia areas (i.e. Thailand and Malaysia). This review describes the current understanding of the genome characteristics, host range, transmission, epidemiology, phylogenetic and immune evasion of avian-origin TMUV and the innate immune response of the host.
    Matched MeSH terms: Genome, Viral/genetics
  15. Fulltext Genome-wide association analyses identify three new susceptibility loci for primary angle closure glaucoma
    Vithana EN, Khor CC, Qiao C, Nongpiur ME, George R, Chen LJ, et al.
    Nat Genet, 2012 Oct;44(10):1142-1146.
    PMID: 22922875 DOI: 10.1038/ng.2390
    Primary angle closure glaucoma (PACG) is a major cause of blindness worldwide. We conducted a genome-wide association study including 1,854 PACG cases and 9,608 controls across 5 sample collections in Asia. Replication experiments were conducted in 1,917 PACG cases and 8,943 controls collected from a further 6 sample collections. We report significant associations at three new loci: rs11024102 in PLEKHA7 (per-allele odds ratio (OR)=1.22; P=5.33×10(-12)), rs3753841 in COL11A1 (per-allele OR=1.20; P=9.22×10(-10)) and rs1015213 located between PCMTD1 and ST18 on chromosome 8q (per-allele OR=1.50; P=3.29×10(-9)). Our findings, accumulated across these independent worldwide collections, suggest possible mechanisms explaining the pathogenesis of PACG.
    Matched MeSH terms: Genome-Wide Association Study*
  16. Comparative genomic and phylogenetic analysis of a toxigenic clinical isolate of Corynebacterium diphtheriae strain B-D-16-78 from Malaysia
    Hong KW, Asmah Hani AW, Nurul Aina Murni CA, Pusparani RR, Chong CK, Verasahib K, et al.
    Infect Genet Evol, 2017 Oct;54:263-270.
    PMID: 28711373 DOI: 10.1016/j.meegid.2017.07.015
    In this study, we report the comparative genomics and phylogenetic analysis of Corynebacterium diphtheriae strain B-D-16-78 that was isolated from a clinical specimen in 2016. The complete genome of C. diphtheriae strain B-D-16-78 was sequenced using PacBio Single Molecule, Real-Time sequencing technology and consists of a 2,474,151-bp circular chromosome with an average GC content of 53.56%. The core genome of C. diphtheriae was also deduced from a total of 74 strains with complete or draft genome sequences and the core genome-based phylogenetic analysis revealed close genetic relationship among strains that shared the same MLST allelic profile. In the context of CRISPR-Cas system, which confers adaptive immunity against re-invading DNA, 73 out of 86 spacer sequences were found to be unique to Malaysian strains which harboured only type-II-C and/or type-I-E-a systems. A total of 48 tox genes which code for the diphtheria toxin were retrieved from the 74 genomes and with the exception of one truncated gene, only nucleotide substitutions were detected when compared to the tox gene sequence of PW8. More than half were synonymous substitution and only two were nonsynonymous substitutions whereby H24Y was predicted to have a damaging effect on the protein function whilst T262V was predicted to be tolerated. Both toxigenic and non-toxigenic toxin-gene bearing strains have been isolated in Malaysia but the repeated isolation of toxigenic strains with the same MLST profile suggests the possibility of some of these strains may be circulating in the population. Hence, efforts to increase herd immunity should be continued and supported by an effective monitoring and surveillance system to track, manage and control outbreak of cases.
    Matched MeSH terms: Genome, Bacterial*
  17. Fulltext Genome-wide mosaicism in divergence between zoonotic malaria parasite subpopulations with separate sympatric transmission cycles
    Divis PCS, Duffy CW, Kadir KA, Singh B, Conway DJ
    Mol Ecol, 2018 02;27(4):860-870.
    PMID: 29292549 DOI: 10.1111/mec.14477
    Plasmodium knowlesi is a significant cause of human malaria transmitted as a zoonosis from macaque reservoir hosts in South-East Asia. Microsatellite genotyping has indicated that human infections in Malaysian Borneo are an admixture of two highly divergent sympatric parasite subpopulations that are, respectively, associated with long-tailed macaques (Cluster 1) and pig-tailed macaques (Cluster 2). Whole-genome sequences of clinical isolates subsequently confirmed the separate clusters, although fewer of the less common Cluster 2 type were sequenced. Here, to analyse population structure and genomic divergence in subpopulation samples of comparable depth, genome sequences were generated from 21 new clinical infections identified as Cluster 2 by microsatellite analysis, yielding a cumulative sample size for this subpopulation similar to that for Cluster 1. Profound heterogeneity in the level of intercluster divergence was distributed across the genome, with long contiguous chromosomal blocks having high or low divergence. Different mitochondrial genome clades were associated with the two major subpopulations, but limited exchange of haplotypes from one to the other was evident, as was also the case for the maternally inherited apicoplast genome. These findings indicate deep divergence of the two sympatric P. knowlesi subpopulations, with introgression likely to have occurred recently. There is no evidence yet of specific adaptation at any introgressed locus, but the recombinant mosaic types offer enhanced diversity on which selection may operate in a currently changing landscape and human environment. Loci responsible for maintaining genetic isolation of the sympatric subpopulations need to be identified in the chromosomal regions showing fixed differences.
    Matched MeSH terms: Genome*
  18. High-throughput terrestrial biodiversity assessments: mitochondrial metabarcoding, metagenomics or metatranscriptomics?
    Wilson JJ, Brandon-Mong GJ, Gan HM, Sing KW
    Mitochondrial DNA A DNA Mapp Seq Anal, 2019 01;30(1):60-67.
    PMID: 29591722 DOI: 10.1080/24701394.2018.1455189
    Consensus on the optimal high-throughput sequencing (HTS) approach to examine biodiversity in mixed terrestrial arthropod samples has not been reached. Metatranscriptomics could increase the proportion of taxonomically informative mitochondrial reads in HTS outputs but has not been investigated for terrestrial arthropod samples. We compared the efficiency of 16S rRNA metabarcoding, metagenomics and metatranscriptomics for detecting species in a mixed terrestrial arthropod sample (pooled DNA/RNA from 38 taxa). 16S rRNA metabarcoding and nuclear rRNA-depleted metatranscriptomics had the highest detection rate with 97% of input species detected. Based on cytochrome c oxidase I, metagenomics had the highest detection rate with 82% of input species detected, but metatranscriptomics produced a larger proportion of reads matching (Sanger) reference sequences. Metatranscriptomics with nuclear rRNA depletion may offer advantages over metabarcoding through reducing the number of spurious operational taxonomic units while retaining high detection rates, and offers natural enrichment of mitochondrial sequences which may enable increased species detection rates compared with metagenomics.
    Matched MeSH terms: Genome, Mitochondrial*
  19. Fulltext Changes in the EV-A71 Genome through Recombination and Spontaneous Mutations: Impact on Virulence
    Mandary MB, Poh CL
    Viruses, 2018 06 12;10(6).
    PMID: 29895721 DOI: 10.3390/v10060320
    Enterovirus 71 (EV-A71) is a major etiological agent of hand, foot and mouth disease (HFMD) that mainly affects young children less than five years old. The onset of severe HFMD is due to neurological complications bringing about acute flaccid paralysis and pulmonary oedema. In this review, we address how genetic events such as recombination and spontaneous mutations could change the genomic organization of EV-A71, leading to an impact on viral virulence. An understanding of the recombination mechanism of the poliovirus and non-polio enteroviruses will provide further evidence of the emergence of novel strains responsible for fatal HFMD outbreaks. We aim to see if the virulence of EV-A71 is contributed solely by the presence of fatal strains or is due to the co-operation of quasispecies within a viral population. The phenomenon of quasispecies within the poliovirus is discussed to reflect viral fitness, virulence and its implications for EV-A71. Ultimately, this review gives an insight into the evolution patterns of EV-A71 by looking into its recombination history and how spontaneous mutations would affect its virulence.
    Matched MeSH terms: Genome, Viral*
  20. Fulltext Evolutionary and genomic analysis of the caleosin/peroxygenase (CLO/PXG) gene/protein families in the Viridiplantae
    Rahman F, Hassan M, Rosli R, Almousally I, Hanano A, Murphy DJ
    PLoS One, 2018;13(5):e0196669.
    PMID: 29771926 DOI: 10.1371/journal.pone.0196669
    Bioinformatics analyses of caleosin/peroxygenases (CLO/PXG) demonstrated that these genes are present in the vast majority of Viridiplantae taxa for which sequence data are available. Functionally active CLO/PXG proteins with roles in abiotic stress tolerance and lipid droplet storage are present in some Trebouxiophycean and Chlorophycean green algae but are absent from the small number of sequenced Prasinophyceaen genomes. CLO/PXG-like genes are expressed during dehydration stress in Charophyte algae, a sister clade of the land plants (Embryophyta). CLO/PXG-like sequences are also present in all of the >300 sequenced Embryophyte genomes, where some species contain as many as 10-12 genes that have arisen via selective gene duplication. Angiosperm genomes harbour at least one copy each of two distinct CLO/PX isoforms, termed H (high) and L (low), where H-forms contain an additional C-terminal motif of about 30-50 residues that is absent from L-forms. In contrast, species in other Viridiplantae taxa, including green algae, non-vascular plants, ferns and gymnosperms, contain only one (or occasionally both) of these isoforms per genome. Transcriptome and biochemical data show that CLO/PXG-like genes have complex patterns of developmental and tissue-specific expression. CLO/PXG proteins can associate with cytosolic lipid droplets and/or bilayer membranes. Many of the analysed isoforms also have peroxygenase activity and are involved in oxylipin metabolism. The distribution of CLO/PXG-like genes is consistent with an origin >1 billion years ago in at least two of the earliest diverging groups of the Viridiplantae, namely the Chlorophyta and the Streptophyta, after the Viridiplantae had already diverged from other Archaeplastidal groups such as the Rhodophyta and Glaucophyta. While algal CLO/PXGs have roles in lipid packaging and stress responses, the Embryophyte proteins have a much wider spectrum of roles and may have been instrumental in the colonisation of terrestrial habitats and the subsequent diversification as the major land flora.
    Matched MeSH terms: Genome/genetics*
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