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  1. Dusfour I, Linton YM, Cohuet A, Harbach RE, Baimai V, Trung HD, et al.
    J Med Entomol, 2004 May;41(3):287-95.
    PMID: 15185927
    Anopheles sundaicus s.l. is a principal malaria vector taxon on islands and along the coastal areas of Southeast Asia. It has a wide geographical distribution and exhibits a high level of ecological and behavioral variability. Study of this taxon is crucial for understanding its biology and implementing effectise vector control measures. We compared populations of An. sundaicus from Vietnam, Thailand, and Malaysian Borneo by using two mitochondrial DNA markers: cytochrome oxidase I and cytochrome b. Genetic divergence, geographic separation, and cladistic analysis of relationships revealed the presence of two cryptic species: Anopheles sundaicus s.s. on Malaysian Borneo and An. sundaicus species A in coastal areas of Thailand and Vietnam. A polymerase chain reaction (PCR) assay was developed to easily identify these two species throughout their geographic distributions. The assay was based on sequence characterized amplified region derived from random amplified polymorphic DNA. This PCR identification method needs to be validated and adapted for the recognition of other possible species in the Sundaicus Complex.
    Matched MeSH terms: DNA, Mitochondrial/genetics*
  2. Loh FK, Nathan S, Chow SC, Fang CM
    Vaccine, 2019 07 09;37(30):3989-4000.
    PMID: 31186188 DOI: 10.1016/j.vaccine.2019.05.083
    Since the discovery of Toxoplasma gondii in 1908, it is estimated that one-third of the global population has been exposed to this ubiquitous intracellular protozoan. The complex life cycle of T. gondii has enabled itself to overcome stress and transmit easily within a broad host range thus achieving a high seroprevalence worldwide. To date, toxoplasmosis remains one of the most prevalent HIV-associated opportunistic central nervous system infections. This review presents a comprehensive overview of different vaccination approaches ranging from traditional inactivated whole-T. gondii vaccines to the popular DNA vaccines. Extensive discussions are made to highlight the challenges in constructing these vaccines, selecting adjuvants as well as delivery methods, immunisation approaches and developing study models. Herein we also deliberate over the latest and promising enhancement strategies that can address the limitations in developing an effective T. gondii prophylactic vaccine.
    Matched MeSH terms: Vaccines, DNA/therapeutic use
  3. Sing CK, Md. Zahirul Islam Khan, Hassan Hj. Mohd Daud, Abd. Rahman Aziz
    Sains Malaysiana, 2016;45:1597-1602.
    The present study was conducted to determine the prevalence and antibiotic resistance of Salmonella sp. isolated from
    African catfish (Clarias gariepinus). A total of 30 catfish were harvested from four different farms and four different
    wet markets. A total of 60 samples (30 catfish skins and 30 catfish intestines) were used for Salmonella sp. isolation
    (pellet-method), its biochemical and serological test. Confirmation of Salmonella sp. were determined by polyvalent
    O antisera and polymerase chain reaction (PCR) using genus specific primers for invA genes (DNA amplification
    showed one distinct band with molecular weight of 389 bp) and the species of isolated Salmonella sp. were identified
    by serotyping. The result showed 6/30 (20%) of fish or 6/60 (10%) of organ samples were positive for Salmonella sp.
    Among those positive for Salmonella sp., 4/6 were from intestine samples and 2/6 were from skin samples. No significant
    difference was found in the prevalence of Salmonella sp. isolates between fish harvested from farms and wet markets
    (p-value= 0.406). The Salmonella serovars identified were Salmonella corvallis (n=3), Salmonella mbandaka (n=2)
    and Salmonella typhmurium (n=1). Salmonella sp. isolates were resistance to Penicillin (P 10, 100%), Clindamycin
    (DA 2, 100%), Tetracycline (TE 30, 100%) and Rifampicin (RD 5, 100%) and all of the isolates were susceptible or
    intermediate resistance to Ceftazidime (CAZ 30) and Trimethopin (W 5). Multiple antibiotic resistance (MAR) index of
    all Salmonella sp. isolates in current study was 0.67 indicating that fish sampled in the present study was under high
    risk of been exposed to the tested antibiotics.
    Matched MeSH terms: DNA; DNA Primers
  4. Koh AE, Alsaeedi HA, Rashid MBA, Lam C, Harun MHN, Saleh MFBM, et al.
    J. Photochem. Photobiol. B, Biol., 2019 Jul;196:111514.
    PMID: 31154277 DOI: 10.1016/j.jphotobiol.2019.111514
    Retinal disorders account for a large proportion of ocular disorders that can lead to visual impairment or blindness, and yet our limited knowledge in the pathogenesis and choice of appropriate animal models for new treatment modalities may contribute to ineffective therapies. Although genetic in vivo models are favored, the variable expressivity and penetrance of these heterogeneous disorders can cause difficulties in assessing potential treatments against retinal degeneration. Hence, an attractive alternative is to develop a chemically-induced model that is both cost-friendly and standardizable. Sodium iodate is an oxidative chemical that is used to simulate late stage retinitis pigmentosa and age-related macular degeneration. In this study, retinal degeneration was induced through systemic administration of sodium iodate (NaIO3) at varying doses up to 80 mg/kg in Sprague-Dawley rats. An analysis on the visual response of the rats by electroretinography (ERG) showed a decrease in photoreceptor function with NaIO3 administration at a dose of 40 mg/kg or greater. The results correlated with the TUNEL assay, which revealed signs of DNA damage throughout the retina. Histomorphological analysis also revealed extensive structural lesions throughout the outer retina and parts of the inner retina. Our results provided a detailed view of NaIO3-induced retinal degeneration, and showed that the administration of 40 mg/kg NaIO3 was sufficient to generate disturbances in retinal function. The pathological findings in this model reveal a degenerating retina, and can be further utilized to develop effective therapies for RPE, photoreceptor, and bipolar cell regeneration.
    Matched MeSH terms: DNA Damage/drug effects
  5. Benavente ED, Gomes AR, De Silva JR, Grigg M, Walker H, Barber BE, et al.
    Sci Rep, 2019 07 08;9(1):9873.
    PMID: 31285495 DOI: 10.1038/s41598-019-46398-z
    The zoonotic Plasmodium knowlesi parasite is the most common cause of human malaria in Malaysia. Genetic analysis has shown that the parasites are divided into three subpopulations according to their geographic origin (Peninsular or Borneo) and, in Borneo, their macaque host (Macaca fascicularis or M. nemestrina). Whilst evidence suggests that genetic exchange events have occurred between the two Borneo subpopulations, the picture is unclear in less studied Peninsular strains. One difficulty is that P. knowlesi infected individuals tend to present with low parasitaemia leading to samples with insufficient DNA for whole genome sequencing. Here, using a parasite selective whole genome amplification approach on unprocessed blood samples, we were able to analyse recent genomes sourced from both Peninsular Malaysia and Borneo. The analysis provides evidence that recombination events are present in the Peninsular Malaysia parasite subpopulation, which have acquired fragments of the M. nemestrina associated subpopulation genotype, including the DBPβ and NBPXa erythrocyte invasion genes. The NBPXb invasion gene has also been exchanged within the macaque host-associated subpopulations of Malaysian Borneo. Our work provides strong evidence that exchange events are far more ubiquitous than expected and should be taken into consideration when studying the highly complex P. knowlesi population structure.
    Matched MeSH terms: DNA, Protozoan/genetics*
  6. Gopal Krishnan S, Fun WH, Ramadras MD, Yunus R, Lye YF, Sararaks S
    PLoS One, 2019;14(7):e0219534.
    PMID: 31291359 DOI: 10.1371/journal.pone.0219534
    BACKGROUND: Developing countries still struggle with late detection and mortality from pertussis. A review of clinical case definitions is necessary for early disease detection. This paper aimed to study possible clinical characteristics for earlier pertussis detection in a sporadic setting.

    METHODS: We conducted a retrospective review of medical and laboratory records in a general paediatric ward of a district hospital in a developing country. Inclusion criteria were all children hospitalised with nasopharyngeal swab taken for Bordetella pertussis. We compared sensitivity and specificity of World Health Organization diagnostic criteria with other clinical characteristics. Polymerase chain reaction Bordetella pertussis was the gold standard used.

    RESULTS: Out of 207 eligible admissions, the study retrieved 128 complete records. Approximately half of the children were less than 3 months old. The World Health Organization diagnostic criteria had a low sensitivity (15%), but high specificity (92%). In comparison, combinations that included paroxysmal cough, ill contact and facial congestion had higher sensitivity. Increasing cough duration improved specificity while compromising sensitivity.

    CONCLUSION: Several clinical characteristics such as paroxysmal cough, facial congestion and a history of ill contact have potential for early clinical detection. Conventional emphasis on cough duration may hamper early detection.

    Matched MeSH terms: DNA, Bacterial/isolation & purification
  7. Kundave VR, Ram H, Shahzad M, Garg R, Banerjee PS, Nehra AK, et al.
    Infect Genet Evol, 2019 11;75:103962.
    PMID: 31302242 DOI: 10.1016/j.meegid.2019.103962
    Genetic characterization of Theileria species infecting bovines in India was attempted targeting the 18S ribosomal RNA region of the parasite. Blood samples of bovines (n = 452), suspected for haemoprotozoan infections, from 9 different states of the country were microscopically examined for Theileria species infection. Four Theileria spp. positive blood samples from each state were randomly utilized for PCR amplification of the 18S rRNA gene (approx. 1529 bp) followed by cloning and sequencing. The sequence data analysis of all the 36 isolates revealed that 33 isolates had high sequence similarity with published sequences of T. annulata, whereas 3 isolates (MF287917, MF287924 and MF287928) showed close similarity with published sequences of T. orientalis. Sequence homology within the isolates ranged between 95.8 and 100% and variation in the length of targeted region was also noticed in different isolates (1527-1538 nt). Phylogenetic tree created for T. annulata sequences revealed that a total of 24 Indian isolates formed a major clade and grouped together with isolates originating from countries like China, Spain, Turkey and USA. Remaining 09 isolates clustered in a separate group and were closely related to the TA5 isolate of T. annulata (a new genotype) originating from India and also with the isolates from East Asian countries like Japan and Malaysia. All the three T. orientalis isolates had minimal intraspecific variation (99-100% homology) amongst themselves. Further, in the phylogenetic analysis T. orientalis Indian isolates were found to cluster away from other 14 isolates of T. buffeli/sergenti/orientalis originating from different countries (Australia, China, Indonesia and Spain). However, these 3 isolates clustered together with the T. buffeli Indian isolate (EF126184). Present study confirmed the circulation of different genotypes of T. annulata in India, along with T. orientalis isolates.
    Matched MeSH terms: DNA, Protozoan/genetics
  8. Amin OM, Chaudhary A, Heckmann RA, Ha NV, Singh HS
    Acta Parasitol, 2019 Dec;64(4):779-796.
    PMID: 31332657 DOI: 10.2478/s11686-019-00102-3
    BACKGROUND: Most (82%) of the 46 recognized species of Acanthogyrus (Acanthosentis) Verma and Datta, 1929 are known from Asian freshwater fishes. Only three species of Acanthosentis are known from marine or brackish water fishes from India and Pakistan. We have discovered another marine species of Acanthosentis in the Pacific Ocean, off Vietnam.

    PURPOSE: The purpose is to describe the new species morphologically and molecularly and provide new information of its evolutionally relationships with other species of the subgenus.

    METHODS: Standard methods of collection and examination of marine hosts, processing and illustrating of specimens, and taxonomic identification of parasites using the extensive collection of the lead author were used. Specimens were further studied using energy-dispersive X-ray analysis and ion sectioning of hooks, SEM analysis, and molecular sequencing. Type specimens were deposited at the Harold W. Manter Lab. collection, Lincoln, Nebraska.

    RESULTS: Acanthogyrus (Acanthosentis) fusiformis n. sp. is described from the catfish, Arius sp. (Ariidae: Siluriformes) off the Pacific Coast of Vietnam at Bac Lieu in the Gulf of Thailand. The three other marine Indian species include A. (A.) arii Bilqees, 1971 which is also described from a similar catfish, Arius serratus Day off the Karachi coast in the Arabian Sea, Indian Ocean. Our new species from Vietnam is distinguished from the other 46 species by a combination of characters including a small fusiform trunk, complete circles of small hollow spines covering the entire trunk, prominent double apical organs often extending posteriorly past posterior hooks, middle and posterior hooks of equal size slightly smaller than anterior hooks, large neck continuous with the outline of the proboscis without distinct separation, big drop-shaped cephalic ganglion, extension of the proboscis receptacle anteriorly past the base of the proboscis up to the insertion point of the posterior hooks, presence of two para-receptacle structures (PRSs), free unattached thick lemnisci, short female reproductive system with filamentous attachment of the distal end of the uterine bell to the ventral body wall, and small narrowly ellipsoid eggs with thickened polar ends. Partial sequences of the 18S and internal transcribed spacers (ITS1-5.8S-ITS2) of ribosomal RNA were generated and used for phylogenetic analyses to confirm the taxonomic identity of Acanthogyrus (Acanthosentis) fusiformis n. sp.

    CONCLUSIONS: We describe unique morphological features of A. fusiformis never before known in the subgenus Acanthosentis. The uniqueness of A. fusiformis is further demonstrated by its EDXA fingerprint characterized by high levels of calcium and phosphorous in hooks. The zoogeography of species of Acanthosentis is elucidated in the Indian subcontinent, the Caribbean, China, and Africa. Molecular data have been available only in few species of Acanthogyrus (Acanthosentis) to date on GenBank database. For 18S, only two sequences from unknown Acanthosentis sp. from India are available, while for the ITS1-5.8S-ITS2 region, only sequences of A. cheni from China and of two unidentified species from Malaysia are available. Additional studies of species of Acanthosentis based on morphological and molecular genetic data will be needed to reconstruct the evolutionary history and phylogenetic affinities of this group of acanthocephalans.

    Matched MeSH terms: DNA, Helminth/genetics
  9. Ramanathan S, Gopinath SCB, Arshad MKM, Poopalan P, Anbu P
    Mikrochim Acta, 2019 07 18;186(8):546.
    PMID: 31321546 DOI: 10.1007/s00604-019-3696-y
    A genomic DNA-based colorimetric assay is described for the detection of the early growth factor receptor (EGFR) mutation, which is the protruding reason for non-small cell lung cancer. A DNA sequence was designed and immobilized on unmodified gold nanoparticles (GNPs). The formation of the respective duplex indicates the presence of an EGFR mutation. It is accompanied by the aggregation of the GNPs in the presence of monovalent ions, and it indicates the presence of an EGFR mutation. This is accompanied by a color change from red (520 nm) to purple (620 nm). Aggregation was evidenced by transmission electron microscopy, scanning electron microscopy and atomic force microscopy. The limit of detection is 313 nM of the mutant target strand. A similar peak shift was observed for 2.5 μM concentrations of wild type target. No significant peak shift was observed with probe and non-complementary DNA. Graphical abstract Schematic representation of high-specific genomic DNA sequence on gold nanoparticle (GNP) aggregation with sodium chloride (NaCl). It illustrates the detection method for EGFR mutation on lung cancer detection. Red and purple colors of tubes represent dispersed and aggregated GNP, respectively.
    Matched MeSH terms: DNA, Single-Stranded/chemistry*
  10. Kongrit C, Markviriya D, Laithong P, Khudamrongsawat J
    Folia Primatol., 2020;91(1):1-14.
    PMID: 31593962 DOI: 10.1159/000500007
    Confiscated slow lorises (Nycticebus spp.) at Bangpra Water-Bird Breeding Center (BWBC) in Thailand provided an opportunity to demonstrate the application of noninvasive genetic approaches for species identification when morphology of the animals was ambiguous. The slow lorises at BWBC had been assigned to either N. bengalensis or N. pygmaeus, based on body size. However, the morphology of N. bengalensis is highly variable and overlaps with that of N. coucang (sensu stricto). Phylogenetic analysis of cytochrome b and d-loop mitochondrial regions placed all confiscated N. pygmaeus with the published sequences of N. pygmaeus and distinguished them from other Nycticebus. All other confiscated individuals formed a monophyletic clade, most individuals grouping with published N. bengalensis sequences from wild populations in Vietnam and distinct from Peninsular Malaysian and Sumatran N. coucang, Javan N. javanicus and Bornean N. menagensis. Six individuals within the N. bengalensis clade formed a separate subgroup that did not group with any reference material as indicated by phylogenetic and haplotype network analyses. Whether these trafficked individuals are undiscovered wild populations will require further investigation. Additional genetic studies of wild slow loris populations in different regions are therefore urgently required for reference to aid the protection and conservation of these threatened species.
    Matched MeSH terms: DNA, Mitochondrial/analysis
  11. Mat Razali N, Cheah BH, Nadarajah K
    Int J Mol Sci, 2019 Jul 23;20(14).
    PMID: 31340492 DOI: 10.3390/ijms20143597
    Transposable elements (TEs) are agents of genetic variability in phytopathogens as they are a source of adaptive evolution through genome diversification. Although many studies have uncovered information on TEs, the exact mechanism behind TE-induced changes within the genome remains poorly understood. Furthermore, convergent trends towards bigger genomes, emergence of novel genes and gain or loss of genes implicate a TE-regulated genome plasticity of fungal phytopathogens. TEs are able to alter gene expression by revamping the cis-regulatory elements or recruiting epigenetic control. Recent findings show that TEs recruit epigenetic control on the expression of effector genes as part of the coordinated infection strategy. In addition to genome plasticity and diversity, fungal pathogenicity is an area of economic concern. A survey of TE distribution suggests that their proximity to pathogenicity genes TEs may act as sites for emergence of novel pathogenicity factors via nucleotide changes and expansion or reduction of the gene family. Through a systematic survey of literature, we were able to conclude that the role of TEs in fungi is wide: ranging from genome plasticity, pathogenicity to adaptive behavior in evolution. This review also identifies the gaps in knowledge that requires further elucidation for a better understanding of TEs' contribution to genome architecture and versatility.
    Matched MeSH terms: DNA Transposable Elements*
  12. Ho CL, Geisler M
    Plants (Basel), 2019 Oct 23;8(11).
    PMID: 31652796 DOI: 10.3390/plants8110441
    The interactions between transcription factors (TFs) and cis-acting regulatory elements (CREs) provide crucial information on the regulation of gene expression. The determination of TF-binding sites and CREs experimentally is costly and time intensive. An in silico identification and annotation of TFs, and the prediction of CREs from rice are made possible by the availability of whole genome sequence and transcriptome data. In this study, we tested the applicability of two algorithms developed for other model systems for the identification of biologically significant CREs of co-expressed genes from rice. CREs were identified from the DNA sequences located upstream from the transcription start sites, untranslated regions (UTRs), and introns, and downstream from the translational stop codons of co-expressed genes. The biologically significance of each CRE was determined by correlating their absence and presence in each gene with that gene's expression profile using a meta-database constructed from 50 rice microarray data sets. The reliability of these methods in the predictions of CREs and their corresponding TFs was supported by previous wet lab experimental data and a literature review. New CREs corresponding to abiotic stresses, biotic stresses, specific tissues, and developmental stages were identified from rice, revealing new pieces of information for future experimental testing. The effectiveness of some-but not all-CREs was found to be affected by copy number, position, and orientation. The corresponding TFs that were most likely correlated with each CRE were also identified. These findings not only contribute to the prioritization of candidates for further analysis, the information also contributes to the understanding of the gene regulatory network.
    Matched MeSH terms: DNA; DNA Copy Number Variations
  13. Lin J, Gopinath SCB, Lakshmipriya T, Chen Y, Yuan WR, Yang M
    Int J Biol Macromol, 2019 Dec 01;141:564-569.
    PMID: 31493451 DOI: 10.1016/j.ijbiomac.2019.09.012
    Human papilloma virus (HPV) affects predominantly the genital area, which includes vagina, cervix, penis, vulva scrotum, rectum and anus. Among 100 types of HPV, 14 types are considered to cause the risky cancer. The gene HPV-16 E7 is responsible for the development of cancer with the infected women. Earlier identification of this gene sequence avoids the cancer progression. The targeted HPV-16 E7 sequence was sandwiched by capture and reporter sequences on the carbodiimidazole-modified interdigitated electrode (IDE) surface. Target sequence at 100 f. was paired to the capture sequence immobilized on IDE sensing surface. To this surface, different concentrations of reporter sequence with and without gold rod (GNR) were evaluated. In both cases the detections were attained 1 aM by the reporter sequence pairing and with GNR increments in current were found. This enhancement was found to be 1000 folds, considering the condition was revealed in the absence of reporter. This sandwich detection strategy of capture-target-reporter sequences for HPV-16 detection on the IDE sensing surface helps to diagnose the association of cervical cancer.
    Matched MeSH terms: DNA, Viral/analysis*
  14. Citartan M, Kaur H, Presela R, Tang TH
    Int J Pharm, 2019 Aug 15;567:118483.
    PMID: 31260780 DOI: 10.1016/j.ijpharm.2019.118483
    Aptamers, nucleic acid ligands that are specific against their corresponding targets are increasingly employed in a variety of applications including diagnostics and therapeutics. The specificity of the aptamers against their targets is also used as the basis for the formulation of the aptamer-based drug delivery system. In this review, we aim to provide an overview on the chaperoning roles of aptamers in acting as the cargo or load carriers, delivering contents to the targeted sites via cell surface receptors. Internalization of the aptamer-biomolecule conjugates via receptor-mediated endocytosis and the strategies to augment the rate of endocytosis are underscored. The cargos chaperoned by aptamers, ranging from siRNAs to DNA origami are illuminated. Possible impediments to the aptamer-based drug deliveries such as susceptibility to nuclease resistance, potentiality for immunogenicity activation, tumor heterogeneity are speculated and the corresponding amendment strategies to address these shortcomings are discussed. We prophesy that the future of the aptamer-based drug delivery will take a trajectory towards DNA nanorobot-based assay.
    Matched MeSH terms: DNA/administration & dosage
  15. Khalil I, Yehye WA, Muhd Julkapli N, Sina AA, Rahmati S, Basirun WJ, et al.
    Analyst, 2020 Feb 17;145(4):1414-1426.
    PMID: 31845928 DOI: 10.1039/c9an02106j
    Surface enhanced Raman scattering (SERS) DNA biosensing is an ultrasensitive, selective, and rapid detection technique with the ability to produce molecule-specific distinct fingerprint spectra. It supersedes the long amplicon based PCR assays, the fluorescence and spectroscopic techniques with their quenching and narrow spectral bandwidth, and the electrochemical detection techniques using multiplexing. However, the performance of the SERS DNA biosensor relies on the DNA probe length, platform composition, both the presence and position of Raman tags and the chosen sensing strategy. In this context, we herein report a SERS biosensor based on dual nanoplatforms with a uniquely designed Raman tag (ATTO Rho6G) intercalated short-length DNA probe for the sensitive detection of the pig species Sus scrofa. In the design of the signal probe (SP), a Raman tag was incorporated adjacent to the spacer arm, followed by a terminal thiol modifier, which consequently had a strong influence on the SERS signal enhancement. The detection strategy involves the probe-target DNA hybridization mediated coupling of the two platforms, i.e., the graphene oxide-gold nanorod (GO-AuNR) functionalized capture probe (CP) and SP-conjugated gold nanoparticles (AuNPs), consequently enhancing the SERS intensity by both the electromagnetic hot spots generated at the junctions or interstices of the two platforms and the chemical enhancement between the AuNPs and the adsorbed intercalated Raman tag. This dual platform based SERS DNA biosensor exhibited outstanding sensitivity in detecting pork DNA with a limit of detection (LOD) of 100 aM validated with DNA extracted from a pork sample (LOD 1 fM). Moreover, the fabricated SERS biosensor showed outstanding selectivity and specificity for differentiating the DNA sequences of six closely related non-target species from the target DNA sequences with single and three nucleotide base-mismatches. Therefore, the developed short-length DNA linked dual platform based SERS biosensor could replace the less sensitive traditional methods of pork DNA detection and be adopted as a universal detection approach for the qualitative and quantitative detection of DNA from any source.
    Matched MeSH terms: DNA/analysis*
  16. Jamaluddin J, Mohd Khair NK, Vinodamaney SD, Othman Z, Abubakar S
    BMC Genet, 2020 01 03;21(1):1.
    PMID: 31900126 DOI: 10.1186/s12863-019-0803-3
    BACKGROUND: C-C motif Chemokine Ligand 3 Like 1 (CCL3L1) is a multiallelic copy number variable, which plays a crucial role in immunoregulatory and hosts defense through the production of macrophage inflammatory protein (MIP)-1α. Variable range of the CCL3L1 copies from 0 to 14 copies have been documented in several different populations. However, there is still lack of report on the range of CCL3L1 copy number exclusively among Malaysians who are a multi-ethnic population. Thus, this study aims to extensively examine the distribution of CCL3L1 copy number in the three major populations from Malaysia namely Malay, Chinese and Indian. A diploid copy number of CCL3L1 for 393 Malaysians (Malay = 178, Indian = 90, and Chinese = 125) was quantified using Paralogue Ratio Tests (PRTs) and then validated with microsatellites analysis.

    RESULTS: To our knowledge, this is the first report on the CCL3L1 copy number that has been attempted among Malaysians and the Chinese ethnic group exhibits a diverse pattern of CCL3L1 distribution copy number from the Malay and Indian (p 

    Matched MeSH terms: DNA Copy Number Variations*
  17. Matsui M, Nishikawa K, Eto K, Hossman MY
    Zoolog Sci, 2020 Feb;37(1):91-101.
    PMID: 32068378 DOI: 10.2108/zs190078
    Two lineages of stream toads in the genus Ansonia from Malaysian Borneo have long been suspected to be specifically distinct on the basis of molecular data. We assessed the taxonomic status of these lineages using morphological and additional genetic data. In mtDNA phylogeny, each lineage-one from Bario, Kelabit Highlands of Sarawak, the other from Mt. Mulu of Sarawak and the Crocker Range of Sabah-is separated from other congeners by large genetic distances, comparable with those observed between heterospecific species in the genus. These lineages are also morphologically distinguishable from other species, and are considered to represent valid, independently evolving species. We therefore describe them as A. kelabitensis sp. nov. and A. kanak sp. nov.
    Matched MeSH terms: DNA, Mitochondrial/genetics
  18. Lam JY, Low GK, Chee HY
    PLoS Negl Trop Dis, 2020 02;14(2):e0008074.
    PMID: 32049960 DOI: 10.1371/journal.pntd.0008074
    BACKGROUND: Leptospirosis is often difficult to diagnose because of its nonspecific symptoms. The drawbacks of direct isolation and serological tests have led to the increased development of nucleic acid-based assays, which are more rapid and accurate. A meta-analysis was performed to evaluate the diagnostic accuracy of genetic markers for the detection of Leptospira in clinical samples.

    METHODOLOGY AND PRINCIPLE FINDINGS: A literature search was performed in Scopus, PubMed, MEDLINE and non-indexed citations (via Ovid) by using suitable keyword combinations. Studies evaluating the performance of nucleic acid assays targeting leptospire genes in human or animal clinical samples against a reference test were included. Of the 1645 articles identified, 42 eligible studies involving 7414 samples were included in the analysis. The diagnostic performance of nucleic acid assays targeting the rrs, lipL32, secY and flaB genes was pooled and analyzed. Among the genetic markers analyzed, the secY gene showed the highest diagnostic accuracy measures, with a pooled sensitivity of 0.56 (95% CI: 0.50-0.63), a specificity of 0.98 (95% CI: 0.97-0.98), a diagnostic odds ratio of 46.16 (95% CI: 6.20-343.49), and an area under the curve of summary receiver operating characteristics curves of 0.94. Nevertheless, a high degree of heterogeneity was observed in this meta-analysis. Therefore, the present findings here should be interpreted with caution.

    CONCLUSION: The diagnostic accuracies of the studies examined for each genetic marker showed a significant heterogeneity. The secY gene exhibited higher diagnostic accuracy measures compared with other genetic markers, such as lipL32, flaB, and rrs, but the difference was not significant. Thus, these genetic markers had no significant difference in diagnostic accuracy for leptospirosis. Further research into these genetic markers is warranted.

    Matched MeSH terms: DNA, Bacterial/genetics*
  19. Mat Jaafar TNA, Taylor MI, Mohd Nor SA, Bruyn M, Carvalho GR
    J Fish Biol, 2020 Feb;96(2):337-349.
    PMID: 31721192 DOI: 10.1111/jfb.14202
    We examine genetic structuring in three commercially important species of the teleost family Carangidae from Malaysian waters: yellowtail scad Atule mate, bigeye scad Selar crumenophthalmus and yellowstripe scad Selaroides leptolepis, from the Indo-Malay Archipelago. In view of their distribution across contrasting habitats, we tested the hypothesis that pelagic species display less genetic divergence compared with demersal species, due to their potential to undertake long-distance migrations in oceanic waters. To evaluate population genetic structure, we sequenced two mitochondrial (mt)DNA [650 bp of cytochrome oxidase I (coI), 450 bp of control region (CR)] and one nuclear gene (910 bp of rag1) in each species. One hundred and eighty samples from four geographical regions within the Indo-Malay Archipelago including a population of yellowtail from Kuwait were examined. Findings revealed that the extent of genetic structuring among populations in the semi-pelagic and pelagic, yellowtail and bigeye were lower than demersal yellowstripe, consistent with the hypothesis that pelagic species display less genetic divergence compared with demersal species. The yellowtail phylogeny identified three distinct clades with bootstrap values of 86%-99% in mtDNA and 63%-67% in rag1. However, in bigeye, three clades were also observed from mtDNA data while only one clade was identified in rag1 dataset. In yellowstripe, the mtDNA tree was split into three closely related clades and two clades in rag1 tree with bootstraps value of 73%-99% and 56% respectively. However, no geographic structure appears in both mtDNA and rag1 datasets. Hierarchical molecular variance analysis (AMOVA), pair wise FST comparisons and the nearest-neighbour statistic (Snn ) showed significant genetic differences among Kuwait and Indo-Malay yellowtail. Within the Indo-Malay Archipelago itself, two distinct mitochondrial lineages were detected in yellowtail suggesting potential cryptic species. Findings suggests varying degrees of genetic structuring, key information relevant to management of exploited stocks, though more rapidly evolving genetic markers should be used in future to better delimit the nature and dynamics of putative stock boundaries.
    Matched MeSH terms: DNA, Mitochondrial/genetics
  20. Zhao K, Ishida Y, Green CE, Davidson AG, Sitam FAT, Donnelly CL, et al.
    J Hered, 2019 12 17;110(7):761-768.
    PMID: 31674643 DOI: 10.1093/jhered/esz058
    Illegal hunting is a major threat to the elephants of Africa, with more elephants killed by poachers than die from natural causes. DNA from tusks has been used to infer the source populations for confiscated ivory, relying on nuclear genetic markers. However, mitochondrial DNA (mtDNA) sequences can also provide information on the geographic origins of elephants due to female elephant philopatry. Here, we introduce the Loxodonta Localizer (LL; www.loxodontalocalizer.org), an interactive software tool that uses a database of mtDNA sequences compiled from previously published studies to provide information on the potential provenance of confiscated ivory. A 316 bp control region sequence, which can be readily generated from DNA extracted from ivory, is used as a query. The software generates a listing of haplotypes reported among 1917 African elephants in 24 range countries, sorted in order of similarity to the query sequence. The African locations from which haplotype sequences have been previously reported are shown on a map. We demonstrate examples of haplotypes reported from only a single locality or country, examine the utility of the program in identifying elephants from countries with varying degrees of sampling, and analyze batches of confiscated ivory. The LL allows for the source of confiscated ivory to be assessed within days, using widely available molecular methods that do not depend on a particular platform or laboratory. The program enables identification of potential regions or localities from which elephants are being poached, with capacity for rapid identification of populations newly or consistently targeted by poachers.
    Matched MeSH terms: DNA, Mitochondrial*
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