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  1. Bizhanova N, Nanova O, Fadakar D, Grachev A, Hong Z, Mohd Sah SA, et al.
    Sci Rep, 2024 Mar 02;14(1):5186.
    PMID: 38431728 DOI: 10.1038/s41598-024-55807-x
    The Eurasian lynx (Lynx lynx) exhibits geographic variability and phylogenetic intraspecific relationships. Previous morphological studies have suggested the existence of multiple lynx subspecies, but recent genetic research has questioned this classification, particularly in Central Asia. In this study, we aimed to analyse the geographic and genetic variation in Central Asian lynx populations, particularly the Turkestan lynx and Altai lynx populations, using morphometric data and mtDNA sequences to contribute to their taxonomic classification. The comparative analysis of morphometric data revealed limited clinal variability between lynx samples from the Altai and Tien Shan regions. By examining mtDNA fragments (control region and cytochrome b) obtained from Kazakhstani lynx populations, two subspecies were identified: L. l. isabellinus (represented by a unique haplotype of the South clade, H46) and L. l. wrangeli (represented by haplotypes H36, H45, and H47 of the East clade). L. l. isabellinus was recognized only in Tien Shan Mountain, while Altai lynx was likely identical to L. l. wrangeli and found in northern Kazakhstan, Altai Mountain, Saur and Tarbagatai Mountains, and Tien Shan Mountain. The morphological and mtDNA evidence presented in this study, although limited in sample size and number of genetic markers, renders the differentiation of the two subspecies challenging. Further sampling and compilation of whole-genome sequencing data are necessary to confirm whether the proposed subspecies warrant taxonomic standing.
    Matched MeSH terms: Genetic Variation*
  2. Li LF, Pusadee T, Wedger MJ, Li YL, Li MR, Lau YL, et al.
    Nat Commun, 2024 Feb 21;15(1):1182.
    PMID: 38383554 DOI: 10.1038/s41467-024-45447-0
    High reproductive compatibility between crops and their wild relatives can provide benefits for crop breeding but also poses risks for agricultural weed evolution. Weedy rice is a feral relative of rice that infests paddies and causes severe crop losses worldwide. In regions of tropical Asia where the wild progenitor of rice occurs, weedy rice could be influenced by hybridization with the wild species. Genomic analysis of this phenomenon has been very limited. Here we use whole genome sequence analyses of 217 wild, weedy and cultivated rice samples to show that wild rice hybridization has contributed substantially to the evolution of Southeast Asian weedy rice, with some strains acquiring weed-adaptive traits through introgression from the wild progenitor. Our study highlights how adaptive introgression from wild species can contribute to agricultural weed evolution, and it provides a case study of parallel evolution of weediness in independently-evolved strains of a weedy crop relative.
    Matched MeSH terms: Genetic Variation*
  3. Abuelmaali SA, Mashlawi AM, Ishak IH, Wajidi MFF, Jaal Z, Avicor SW, et al.
    Sci Rep, 2024 Feb 05;14(1):2978.
    PMID: 38316804 DOI: 10.1038/s41598-024-52591-6
    Although knowledge of the composition and genetic diversity of disease vectors is important for their management, this is limiting in many instances. In this study, the population structure and phylogenetic relationship of the two Aedes aegypti subspecies namely Aedes aegypti aegypti (Aaa) and Aedes aegypti formosus (Aaf) in eight geographical areas in Sudan were analyzed using seven microsatellite markers. Hardy-Weinberg Equilibrium (HWE) for the two subspecies revealed that Aaa deviated from HWE among the seven microsatellite loci, while Aaf exhibited departure in five loci and no departure in two loci (A10 and M201). The Factorial Correspondence Analysis (FCA) plots revealed that the Aaa populations from Port Sudan, Tokar, and Kassala clustered together (which is consistent with the unrooted phylogenetic tree), Aaf from Fasher and Nyala populations clustered together, and Gezira, Kadugli, and Junaynah populations also clustered together. The Bayesian cluster analysis structured the populations into two groups suggesting two genetically distinct groups (subspecies). Isolation by distance test revealed a moderate to strong significant correlation between geographical distance and genetic variations (p = 0.003, r = 0.391). The migration network created using divMigrate demonstrated that migration and gene exchange between subspecies populations appear to occur based on their geographical proximity. The genetic structure of the Ae. aegypti subspecies population and the gene flow among them, which may be interpreted as the mosquito vector's capacity for dispersal, were revealed in this study. These findings will help in the improvement of dengue epidemiology research including information on the identity of the target vector/subspecies and the arboviruses vector surveillance program.
    Matched MeSH terms: Genetic Variation
  4. Hew YX, Ya'cob Z, Chen CD, Lau KW, Sofian-Azirun M, Muhammad-Rasul AH, et al.
    Acta Trop, 2024 Feb;250:107097.
    PMID: 38097150 DOI: 10.1016/j.actatropica.2023.107097
    Mitochondrial cytochrome c oxidase subunit I (COI) sequences were utilized to infer the population genetic structure of Simulium (Gomphostilbia) atratum De Meijere, an endemic simulid species to Indonesia. Both median-joining haplotype network and maximum-likelihood tree revealed two genetic lineages (A and B) within the species, with an overlap distribution in Lombok, which is situated along Wallace's line. Genetic differentiation and gene flow with varying frequencies (FST = 0.02-0.967; Nm = 0.01-10.58) were observed between populations of S. (G.) atratum, of which population pairs of different lineages showed high genetic differentiation. Notably, the high genetic distance of up to 5.92 % observed within S. (G.) atratum in Lombok was attributed to the existence of two genetically distinct lineages. The co-occurrence of distinct lineages in Lombok indicated that Wallace's line did not act as faunistic border for S. (G.) atratum in the present study. Moreover, both lineages also exhibited unimodal distributions and negative values of neutrality tests, suggesting a pattern of population expansion. The expansion and divergence time estimation suggested that the two lineages of S. (G.) atratum diverged and expanded during the Pleistocene era in Indonesia.
    Matched MeSH terms: Genetic Variation
  5. Latif ENM, Noordin NR, Shahari S, Amir A, Lau YL, Cheong FW, et al.
    Parasitol Res, 2024 Jan 19;123(1):105.
    PMID: 38240877 DOI: 10.1007/s00436-024-08125-0
    Plasmodium cynomolgi is a simian malaria parasite that has been increasingly infecting humans. It is naturally present in the long-tailed and pig-tailed macaques in Southeast Asia. The P. cynomolgi Duffy binding protein 1 region II [PcDBP1(II)] plays an essential role in the invasion of the parasite into host erythrocytes. This study investigated the genetic polymorphism, natural selection and haplotype clustering of PcDBP1(II) from wild macaque isolates in Peninsular Malaysia. The genomic DNA of 50 P. cynomolgi isolates was extracted from the macaque blood samples. Their PcDBP1(II) gene was amplified using a semi-nested PCR, cloned into a plasmid vector and subsequently sequenced. The polymorphism, natural selection and haplotypes of PcDBP1(II) were analysed using MEGA X and DnaSP ver.6.12.03 programmes. The analyses revealed high genetic polymorphism of PcDBP1(II) (π = 0.026 ± 0.004; Hd = 0.996 ± 0.001), and it was under purifying (negative) selection. A total of 106 haplotypes of PcDBP1(II) were identified. Phylogenetic and haplotype analyses revealed two groups of PcDBP1(II). Amino acid length polymorphism was observed between the groups, which may lead to possible phenotypic difference between them.
    Matched MeSH terms: Genetic Variation
  6. Fam YQ, Jamaluddin JAF, Muhammad-Rasul AH, Ilham-Norhakim ML, Rosely NFN, Lavoué S
    J Fish Biol, 2024 Jan;104(1):171-183.
    PMID: 37775959 DOI: 10.1111/jfb.15572
    The variability in the stenotopic miniature rasborine Boraras maculatus (Cypriniformes: Danionidae: Rasborinae) across acidic-water habitats of Peninsular Malaysia (PM) was investigated using two molecular markers (the mitochondrial cytochrome c oxidase subunit I [COI] gene and the nuclear rhodopsin gene), as well as morphological evidence. Molecular phylogenetic analyses revealed differentiation among populations of B. maculatus in PM with the distinction of four allopatric lineages. Each of them was recognized as a putative species by automatic species delimitation methods. These lineages diverged from each other between 7.4 and 1.9 million years ago. A principal component analysis (PCA) was conducted to examine the multivariate variation in 11 morphometric measurements among three of these lineages. PCA results showed a significant overlap in morphological characteristics among these lineages. Additionally, a photograph-based machine learning approach failed to fully differentiate these lineages, suggesting limited morphological differentiation. B. maculatus represents a case of morphological stasis in a stenotopic miniature species. Strong habitat preference, coupled with long-term habitat fragmentation, may explain why each lineage of B. maculatus has a restricted distribution and did not disperse to other regions within and outside of PM, despite ample possibilities when the Sunda shelf was emerged and drained by large paleodrainages for most of the past 7 million years. The conservation status of B. maculatus and its peat swamp habitats are discussed, and it is concluded that peat swamps comprise several evolutionary units. Each of these units is considered a conservation unit and deserves appropriate protection.
    Matched MeSH terms: Genetic Variation
  7. Trop Biomed, 2023 Dec 01;40(4):375-382.
    PMID: 38308823 DOI: 10.47665/tb.40.4.001
    Bovine anaplasmosis, caused by Anaplasma marginale, is a significant infectious disease affecting cattle populations globally. However, the prevalence and distribution of bovine anaplasmosis vary across regions, making it crucial to assess its global burden systematically. This study aims to provide a comprehensive understanding of the global prevalence of bovine anaplasmosis and synthesized data from diverse geographic regions. A literature search was conducted to identify all relevant published articles reporting the prevalence of bovine anaplasmosis and a total of 164 studies were found eligible for final systematic review and meta-analysis. Meta-analysis was conducted using meta package of R software and summary estimates of the prevalence were calculated. Meta-analysis of 129,851 samples from 42 countries was conducted and the overall estimated prevalence of bovine anaplasmosis was found to be 38% (100% CI = 33% - 42%). The prevalence was found to be higher in cattle (39.9%) in comparison to yaks (6.4%). Diagnosis using serology (40.2%) yielded a higher prevalence compared to molecular testing (38.3%) and blood smears (22.4%) methods. Additionally, there were significant differences in the prevalence of bovine anaplasmosis between different countries (p<0.05). This study will inform evidence-based strategies for control and prevention of bovine anaplasmosis on a global scale by discovering the true extent of the disease and identifying high-prevalence areas.
    Matched MeSH terms: Genetic Variation
  8. Tan JH, Ding HX, Fong MY, Lau YL
    Infect Genet Evol, 2023 Oct;114:105490.
    PMID: 37595939 DOI: 10.1016/j.meegid.2023.105490
    Plasmodium knowlesi is the leading cause of malaria in Malaysia. Serine Repeat Antigens (SERAs) have an essential role in the parasite life cycle. However, genetic characterization on P. knowlesi SERA3 Ag2 (PkSERA3 Ag2) is lacking. In the present study, nucleotide diversity, natural selection, and haplotypes of PkSERA3 Ag2 in clinical samples from Peninsular Malaysia and Malaysian Borneo were investigated. A total of 50 P. knowlesi clinical samples were collected from Peninsular Malaysia and Malaysian Borneo. The PkSERA3 Ag2 gene was amplified using PCR, and subsequently cloned and sequenced. Genetic diversity, haplotype, natural selection as well as genetic structure and differentiation of PkSERA3 Ag2 were analysed. In addition, in silico analyses were performed to identify repeat motifs, B-cell epitopes, and antigenicity indices of the protein. Analysis of 114 PkSERA3 Ag2 sequences revealed high nucleotide diversity of the gene in Malaysia. A codon-based Z-test indicated that the gene underwent purifying selection. Haplotype and population structure analyses identified two distinct PkSERA3 Ag2 clusters (K = 2, ΔK = 721.14) but no clear genetic distinction between PkSERA3 Ag2 from Peninsular Malaysia and Malaysian Borneo. FST index indicated moderate differentiation of the gene. In silico analyses revealed unique repeat motifs among PkSERA3 Ag2 isolates. Moreover, the amino acid sequence of PkSERA3 Ag2 exhibited potential B-cell epitopes and possessed high antigenicity indices. These findings enhance the understanding of PkSERA3 Ag2 gene as well as its antigenic properties. Further validation is necessary to ascertain the utility of PkSERA3 Ag2 as a serological marker for P. knowlesi infection.
    Matched MeSH terms: Genetic Variation*
  9. Khan MMH, Rafii MY, Ramlee SI, Jusoh M, Al Mamun M, Kundu BC
    Mol Biol Rep, 2023 Sep;50(9):7619-7637.
    PMID: 37531035 DOI: 10.1007/s11033-023-08693-x
    BACKGROUND: A set of 44 selected Bambara groundnut (Vigna subterranea [L.] Verdc.) accessions was sampled from 11 distinct populations of four geographical zones to assess the genetic drift, population structure, phylogenetic relationship, and genetic differentiation linked with ISSR primers.

    METHODS AND RESULTS: The amplification of genomic DNA with 32 ISSR markers detected an average of 97.64% polymorphism while 35.15% and 51.08% polymorphism per population and geographical zone, respectively. Analysis of molecular variance revealed significant variation within population 75% and between population 25% whereas within region 84% and between region 16%. The Bidillali exposed greater number of locally common band i.e., NLCB (≤ 25%) = 25 and NLCB (≤ 50%) = 115 were shown by Cancaraki while the lowest was recorded as NLCB (≤ 25%) = 6 and NLCB (≤ 50%) = 72 for Roko and Maibergo, accordingly. The highest PhiPT value was noted between Roko and Katawa (0.405*) whereas Nei's genetic distance was maximum between Roko and Karu (0.124). Based on Nei's genetic distance, a radial phylogenetic tree was constructed that assembled the entire accessions into 3 major clusters for further confirmation unrooted NJ vs NNet split tree analysis based on uncorrected P distance exposed the similar result. Principal coordinate analysis showed variation as PC1 (15.04%) > PC2 (5.81%).

    CONCLUSIONS: The current study leads to prompting the genetic improvement and future breeding program by maximum utilization and better conservation of existing accessions. The accessions under Cancaraki and Jatau are population documented for future breeding program due to their higher genetic divergence and homozygosity.

    Matched MeSH terms: Genetic Variation/genetics
  10. Rauff-Adedotun AA, Lee IL, Abd Talib N, Shaari N, Yahaya ZS, Meor Termizi FH
    Parasitol Res, 2023 Sep;122(9):2193-2205.
    PMID: 37462745 DOI: 10.1007/s00436-023-07920-5
    Blastocystis is a unicellular, anaerobic protist inhabiting the intestinal tract of diverse animal hosts, including human. Information regarding Blastocystis in small ruminants, namely goats and sheep, is limited globally; thus, this study was carried out to investigate the distribution and determinants of Blastocystis in ruminant livestock animals from Penang, Malaysia. Fecal samples from 127 cattle, 149 goats, and 100 sheep were examined for Blastocystis by in vitro cultivation using modified Jones' medium, while DNA barcoding was used for subtyping. Overall, 23.1% (87/376) of animals screened were positive for Blastocystis sp. The prevalence of infection was significantly higher in goats than in cattle and sheep, while the female gender, semi-intensive farming system, and the Northeast Penang Island district were identified as potential risk factors for Blastocystis infection. Blastocystis sp. ST5, ST14, and ST25 were identified in cattle; ST5, ST10, ST13, and ST14 in goats; and ST4, ST5, ST14, and ST15 in sheep. ST5 and ST14 were found to be the most abundant and widespread subtypes in the study area. To the best of our knowledge, this is the first report of ST4 from sheep and ST13 from goats, thus serving as an update to the host range of Blastocystis sp. ST4 and ST13. The isolation of ST4 and ST5 in this study suggests that ruminant livestock animals could serve as reservoirs of human infection.
    Matched MeSH terms: Genetic Variation
  11. Turkiewicz A, Manko E, Oresegun DR, Nolder D, Spadar A, Sutherland CJ, et al.
    Sci Rep, 2023 Feb 07;13(1):2142.
    PMID: 36750737 DOI: 10.1038/s41598-023-29368-4
    The zoonotic Plasmodium knowlesi parasite is a growing public health concern in Southeast Asia, especially in Malaysia, where elimination of P. falciparum and P. vivax malaria has been the focus of control efforts. Understanding of the genetic diversity of P. knowlesi parasites can provide insights into its evolution, population structure, diagnostics, transmission dynamics, and the emergence of drug resistance. Previous work has revealed that P. knowlesi fall into three main sub-populations distinguished by a combination of geographical location and macaque host (Macaca fascicularis and M. nemestrina). It has been shown that Malaysian Borneo groups display profound heterogeneity with long regions of high or low divergence resulting in mosaic patterns between sub-populations, with some evidence of chromosomal-segment exchanges. However, the genetic structure of non-Borneo sub-populations is less clear. By gathering one of the largest collections of P. knowlesi whole-genome sequencing data, we studied structural genomic changes across sub-populations, with the analysis revealing differences in Borneo clusters linked to mosquito-related stages of the parasite cycle, in contrast to differences in host-related stages for the Peninsular group. Our work identifies new genetic exchange events, including introgressions between Malaysian Peninsular and M. nemestrina-associated clusters on various chromosomes, including in parasite invasion genes (DBP[Formula: see text], NBPX[Formula: see text] and NBPX[Formula: see text]), and important proteins expressed in the vertebrate parasite stages. Recombination events appear to have occurred between the Peninsular and M. fascicularis-associated groups, including in the DBP[Formula: see text] and DBP[Formula: see text] invasion associated genes. Overall, our work finds that genetic exchange events have occurred among the recognised contemporary groups of P. knowlesi parasites during their evolutionary history, leading to apparent mosaicism between these sub-populations. These findings generate new hypotheses relevant to parasite evolutionary biology and P. knowlesi epidemiology, which can inform malaria control approaches to containing the impact of zoonotic malaria on human communities.
    Matched MeSH terms: Genetic Variation
  12. García-Berro A, Talla V, Vila R, Wai HK, Shipilina D, Chan KG, et al.
    Mol Ecol, 2023 Feb;32(3):560-574.
    PMID: 36336800 DOI: 10.1111/mec.16770
    Migration is typically associated with risk and uncertainty at the population level, but little is known about its cost-benefit trade-offs at the species level. Migratory insects in particular often exhibit strong demographic fluctuations due to local bottlenecks and outbreaks. Here, we use genomic data to investigate levels of heterozygosity and long-term population size dynamics in migratory insects, as an alternative to classical local and short-term approaches such as regional field monitoring. We analyse whole-genome sequences from 97 Lepidoptera species and show that individuals of migratory species have significantly higher levels of genome-wide heterozygosity, a proxy for effective population size, than do nonmigratory species. Also, we contribute whole-genome data for one of the most emblematic insect migratory species, the painted lady butterfly (Vanessa cardui), sampled across its worldwide distributional range. This species exhibits one of the highest levels of genomic heterozygosity described in Lepidoptera (2.95 ± 0.15%). Coalescent modelling (PSMC) shows historical demographic stability in V. cardui, and high effective population size estimates of 2-20 million individuals 10,000 years ago. The study reveals that the high risks associated with migration and local environmental fluctuations do not seem to decrease overall genetic diversity and demographic stability in migratory Lepidoptera. We propose a "compensatory" demographic model for migratory r-strategist organisms in which local bottlenecks are counterbalanced by reproductive success elsewhere within their typically large distributional ranges. Our findings highlight that the boundaries of populations are substantially different for sedentary and migratory insects, and that, in the latter, local and even regional field monitoring results may not reflect whole population dynamics. Genomic diversity patterns may elucidate key aspects of an insect's migratory nature and population dynamics at large spatiotemporal scales.
    Matched MeSH terms: Genetic Variation/genetics
  13. Attah AO, Sanggari A, Li LI, Nik Him NAII, Ismail AH, Meor Termizi FH
    Parasitol Res, 2023 Jan;122(1):1-10.
    PMID: 36434314 DOI: 10.1007/s00436-022-07731-0
    There has been increasing interest in the study of Blastocystis in the last two decades. Many studies have been carried out in human and animal hosts including environmental sources, but there is little or no information on the occurrence of Blastocystis in water sources worldwide. Therefore, this study aimed at assessing the occurrence of Blastocystis in water sources across the world from 2005 to 2022, noting the method of detection and the distribution of the subtypes from various water sources. A literature search was performed on internet-based databases including Google search, PubMed, Scopus, and Web of Science. Upon application of the criteria for inclusion, 25 articles revealing the occurrence of Blastocystis in water sources in 15 countries were included in the review. Blastocystis occurrence varies across water sources ranging from 0% in a drinking water source in Venezuela to 100% in rivers; well water, stored water, and fishpond in Nepal and Malaysia; and fountain water, irrigation water, and rainwater in Italy, Spain, and Thailand. The occurrence of the parasite was significantly associated with the coliform count, temperature, conductivity, dissolved oxygen, turbidity, total dissolved solids, and chemical oxygen demand. A total of 11 Blastocystis subtypes were identified in water sources worldwide, namely, ST1-ST8, ST10, ST23, and ST26 in which ST1 and ST3 were the most prevalent subtypes. Considering the importance of Blastocystis as a waterborne parasite, the subtype distribution and morphological distinction in water sources need to be carried out using molecular and electron microscopic techniques. Existing studies have covered only about 10% of the world's countries.
    Matched MeSH terms: Genetic Variation
  14. Ng YL, Lau YL, Hamid MHA, Jelip J, Ooi CH, Mudin RN, et al.
    Parasitol Res, 2023 Jan;122(1):195-200.
    PMID: 36378331 DOI: 10.1007/s00436-022-07716-z
    Plasmodium knowlesi is a simian malaria parasite that causes significant zoonotic infections in Southeast Asia, particularly in Malaysia. The Plasmodium thrombospondin-related apical merozoite protein (TRAMP) plays an essential role in the invasion of the parasite into its host erythrocyte. The present study investigated the genetic polymorphism and natural selection of the full length PkTRAMP from P. knowlesi clinical isolates from Malaysia. Blood samples (n = 40) were collected from P. knowlesi malaria patients from Peninsular Malaysia and Malaysian Borneo. The PkTRAMP gene was amplified using PCR, followed by cloning into a plasmid vector and sequenced. Results showed that the nucleotide diversity of PkTRAMP was low (π: 0.009). Z-test results indicated negative (purifying) selection of PkTRAMP. The alignment of the deduced amino acid sequences of PkTRAMP of Peninsular Malaysia and Malaysian Borneo revealed 38 dimorphic sites. A total of 27 haplotypes were identified from the amino acid sequence alignment. Haplotype analysis revealed that there was no clustering of PkTRAMP from Peninsular Malaysia and Malaysian Borneo.
    Matched MeSH terms: Genetic Variation
  15. Vankova OE, Brusnigina NF, Novikova NA
    Sovrem Tekhnologii Med, 2023;15(2):41-46.
    PMID: 37389021 DOI: 10.17691/stm2023.15.2.04
    Modern molecular genetic methods, massive parallel sequencing in particular, allow for genotyping of various pathogens with the aim of their epidemiological marking and improvement of molecular epidemiological surveillance of actual infections, including cytomegalovirus infection. The aim of the study is to evaluate the next-generation sequencing (NGS) technology for genotyping clinical isolates of cytomegalovirus (CMV).

    MATERIALS AND METHODS: The object of the study were samples of biological substrates (leukocyte mass, saliva, urine) taken from patients who underwent liver and kidney transplantation. Detection of CMV DNA was carried out by a real-time PCR using commercial diagnostic AmpliSense CMV-FL test systems (Central Research Institute for Epidemiology, Moscow, Russia). DNA extraction was performed using DNA-sorb AM and DNA-sorb V kits (Central Research Institute for Epidemiology) in accordance with manufacturer's manual. The quality of the prepared DNA library for sequencing was assessed by means of the QIAxcel Advanced System capillary gel electrophoresis system (QIAGEN, Germany). Alignment and assembly of nucleotide sequences were carried out using CLC Genomics Workbench 5.5 software (CLC bio, USA). The sequencing results were analyzed using BLAST of NCBI server.

    RESULTS: CMV DNA samples were selected for genotyping. The two variable genes, UL55(gB) and UL73(gN), were used for CMV genotype determination, which was performed using NGS technology MiSeq sequencer (Illumina, USA). Based on the exploratory studies and analysis of literature sources, primers for genotyping on the UL55(gB) and UL73(gN) genes have been selected and the optimal conditions for the PCR reaction have been defined. The results of sequencing the UL55(gB) and UL73(gN) gene fragments of CMV clinical isolates from recipients of solid organs made it possible to determine the virus genotypes, among which gB2, gN4c, and gN4b were dominant. In some cases, association of two and three CMV genotypes has been revealed.

    CONCLUSION: The application of the NGS technology for genotyping cytomegalovirus strains can become one of the main methods of CMV infection molecular epidemiology, as it allows for obtaining reliable results with a significant reduction in research time.

    Matched MeSH terms: Genetic Variation/genetics
  16. Azlan UW, Lau YL, Fong MY
    Korean J Parasitol, 2022 Dec;60(6):393-400.
    PMID: 36588415 DOI: 10.3347/kjp.2022.60.6.393
    Human infection with simian malaria Plasmodium knowlesi is a cause for concern in Southeast Asian countries, especially in Malaysia. A previous study on Peninsular Malaysia P. knowlesi rhoptry associated protein-1 (PkRAP1) gene has discovered the existence of dimorphism. In this study, genetic analysis of PkRAP1 in a larger number of P. knowlesi samples from Malaysian Borneo was conducted. The PkRAP1 of these P. knowlesi isolates was PCR-amplified and sequenced. The newly obtained PkRAP1 gene sequences (n = 34) were combined with those from the previous study (n = 26) and analysed for polymorphism and natural selection. Sequence analysis revealed a higher genetic diversity of PkRAP1 compared to the previous study. Exon II of the gene had higher diversity (π = 0.0172) than exon I (π = 0.0128). The diversity of the total coding region (π = 0.0167) was much higher than those of RAP1 orthologues such as PfRAP-1 (π = 0.0041) and PvRAP1 (π = 0.00088). Z-test results indicated that the gene was under purifying selection. Phylogenetic tree and haplotype network showed distinct clustering of Peninsular Malaysia and Malaysian Borneo PkRAP1 haplotypes. This geographical-based clustering of PkRAP1 haplotypes provides further evidence of the dimorphism of the gene and possible existence of 2 distinct P. knowlesi lineages in Malaysia.
    Matched MeSH terms: Genetic Variation*
  17. Nasir MH, Bhassu S, Mispan MS, Bakar SA, Jing KJ, Omar H
    Zoolog Sci, 2022 Dec;39(6):554-561.
    PMID: 36495490 DOI: 10.2108/zs210093
    Rats (Rattus species) are the most notorious vertebrate pests in Malaysian oil palm plantations. Although many studies have been conducted on Asian rats, little attention has been paid to their species composition and phylogenetic relationships in oil palm plantations in Peninsular Malaysia. We determined the mitochondrial cytochrome oxidase subunit I (COI) gene sequence (708 bp) for 216 individual rats collected from five oil palm plantations in Peninsular Malaysia. Phylogenetic analysis in conjunction with comparison with sequences from the nucleotide sequence database revealed five distinct lineages in the Malaysian oil plantations: Rattus tiomanicus, Rattus argentiventer, Rattus exulans, Rattus tanezumi, and a taxon corresponding to the Malayan house rat, which was most frequently observed (∼50%). The last taxon has traditionally been classified as a synonym of Rattus rattus (Rattus rattus diardii) or Rattus tanezumi, but our phylogenetic analysis placed it as an independent lineage, which is not particularly closely related to R. rattus or R. tanezumi, and which we refer to as Rattus diardii. The construction of the network showed that there is considerable genetic variation within the lineages of R. diardii and R tiomanicus, suggesting that these two species are native to the Malay Peninsula.
    Matched MeSH terms: Genetic Variation
  18. Azlan UW, Lau YL, Hamid MHA, Jelip J, Ooi CH, Mudin RN, et al.
    Trop Biomed, 2022 Dec 01;39(4):504-510.
    PMID: 36602208 DOI: 10.47665/tb.39.4.006
    The Plasmodium knowlesi secreted protein with an altered thrombospondin repeat (PkSPATR) is an important protein that helps in the parasite's invasion into the host cell. This protein has been regarded as one of the potential vaccine candidates against P. knowlesi infection. This study investigates the genetic diversity and natural selection of PkSPATR gene of P. knowlesi clinical isolates from Malaysia. PCR amplification of the full length PkSPATR gene was performed on 60 blood samples of infected P. knowlesi patients from Peninsular Malaysia and Malaysian Borneo. The amplified PCR products were cloned and sequenced. Sequence analysis of PkSPATR from Malaysia showed higher nucleotide diversity (CDS p: 0.01462) than previously reported Plasmodium vivax PvSPATR (p = 0.0003). PkSPATR from Peninsular Malaysia was observed to have slightly higher diversity (CDS p: 0.01307) than those from Malaysian Borneo (CDS p: 0.01212). Natural selection analysis on PkSPATR indicated significant purifying selection. Multiple amino acid sequence alignment revealed 69 polymorphic sites. The phylogenetic tree and haplotype network did not show any distinct clustering of PkSPATR. The low genetic diversity level, natural selection and absence of clustering implied functional constrains of the PkSPATR protein.
    Matched MeSH terms: Genetic Variation
  19. Chamchoy K, Sudsumrit S, Thita T, Krudsood S, Patrapuvich R, Boonyuen U
    PLoS Negl Trop Dis, 2022 Dec;16(12):e0010986.
    PMID: 36508454 DOI: 10.1371/journal.pntd.0010986
    BACKGROUND: Primaquine and tafenoquine are the only licensed drugs that effectively kill the hypnozoite stage and are used to prevent Plasmodium vivax malaria relapse. However, both primaquine and tafenoquine can cause acute hemolysis in glucose-6-phosphate dehydrogenase (G6PD)-deficient people with varying degrees of severity depending on G6PD variants. Additionally, primaquine efficacy against malaria parasites was decreased in individuals with impaired cytochrome P450 2D6 (CYP2D6) activity due to genetic polymorphisms. This study aimed to characterize G6PD and CYP2D6 genetic variations in vivax malaria patients from Yala province, a malaria-endemic area along the Thai-Malaysian border, and determine the biochemical properties of identified G6PD variants.

    METHODOLOGY/PRINCIPLE FINDINGS: Multiplexed high-resolution melting assay and DNA sequencing detected five G6PD variants, including G6PD Kaiping, G6PD Vanua Lava, G6PD Coimbra, G6PD Mahidol, and G6PD Kerala-Kalyan. Biochemical and structural characterization revealed that G6PD Coimbra markedly reduced catalytic activity and structural stability, indicating a high susceptibility to drug-induced hemolysis. While Kerala-Kalyan had minor effects, it is possible to develop mild adverse effects when receiving radical treatment. CYP2D6 genotyping was performed using long-range PCR and DNA sequencing, and the phenotypes were predicted using the combination of allelic variants. Decreased and no-function alleles were detected at frequencies of 53.4% and 14.2%, respectively. The most common alleles were CYP2D6*36+*10 (25.6%), *10 (23.9%), and *1 (22.2%). Additionally, 51.1% of the intermediate metabolizers showed CYP2D6*10/*36+*10 as the predominant genotype (15.9%).

    CONCLUSIONS/SIGNIFICANCE: Our findings provide insights about genetic variations of G6PD and CYP2D6 in 88 vivax malaria patients from Yala, which may influence the safety and effectiveness of radical treatment. Optimization of 8-aminoquinoline administration may be required for safe and effective treatment in the studied population, which could be a significant challenge in achieving the goal of eliminating malaria.

    Matched MeSH terms: Genetic Variation
  20. Pekar JE, Magee A, Parker E, Moshiri N, Izhikevich K, Havens JL, et al.
    Science, 2022 Aug 26;377(6609):960-966.
    PMID: 35881005 DOI: 10.1126/science.abp8337
    Understanding the circumstances that lead to pandemics is important for their prevention. We analyzed the genomic diversity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) early in the coronavirus disease 2019 (COVID-19) pandemic. We show that SARS-CoV-2 genomic diversity before February 2020 likely comprised only two distinct viral lineages, denoted "A" and "B." Phylodynamic rooting methods, coupled with epidemic simulations, reveal that these lineages were the result of at least two separate cross-species transmission events into humans. The first zoonotic transmission likely involved lineage B viruses around 18 November 2019 (23 October to 8 December), and the separate introduction of lineage A likely occurred within weeks of this event. These findings indicate that it is unlikely that SARS-CoV-2 circulated widely in humans before November 2019 and define the narrow window between when SARS-CoV-2 first jumped into humans and when the first cases of COVID-19 were reported. As with other coronaviruses, SARS-CoV-2 emergence likely resulted from multiple zoonotic events.
    Matched MeSH terms: Genetic Variation
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