Displaying publications 1021 - 1040 of 1878 in total

Abstract:
Sort:
  1. Krzeminska U, Wilson R, Rahman S, Song BK, Seneviratne S, Gan HM, et al.
    Mitochondrial DNA A DNA Mapp Seq Anal, 2016 Jul;27(4):2668-70.
    PMID: 26075478 DOI: 10.3109/19401736.2015.1043540
    The complete mitochondrial genomes of two jungle crows (Corvus macrorhynchos) were sequenced. DNA was extracted from tissue samples obtained from shed feathers collected in the field in Sri Lanka and sequenced using the Illumina MiSeq Personal Sequencer. Jungle crow mitogenomes have a structural organization typical of the genus Corvus and are 16,927 bp and 17,066 bp in length, both comprising 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal subunit genes, and a non-coding control region. In addition, we complement already available house crow (Corvus spelendens) mitogenome resources by sequencing an individual from Singapore. A phylogenetic tree constructed from Corvidae family mitogenome sequences available on GenBank is presented. We confirm the monophyly of the genus Corvus and propose to use complete mitogenome resources for further intra- and interspecies genetic studies.
    Matched MeSH terms: Phylogeny
  2. Wasitthankasem R, Vongpunsawad S, Siripon N, Suya C, Chulothok P, Chaiear K, et al.
    PLoS One, 2015;10(5):e0126764.
    PMID: 25962112 DOI: 10.1371/journal.pone.0126764
    The majority of hepatitis C virus (HCV) infection results in chronic infection, which can lead to liver cirrhosis and hepatocellular carcinoma. Global burden of hepatitis C virus (HCV) is estimated at 150 million individuals, or 3% of the world's population. The distribution of the seven major genotypes of HCV varies with geographical regions. Since Asia has a high incidence of HCV, we assessed the distribution of HCV genotypes in Thailand and Southeast Asia. From 588 HCV-positive samples obtained throughout Thailand, we characterized the HCV 5' untranslated region, Core, and NS5B regions by nested PCR. Nucleotide sequences obtained from both the Core and NS5B of these isolates were subjected to phylogenetic analysis, and genotypes were assigned using published reference genotypes. Results were compared to the epidemiological data of HCV genotypes identified within Southeast Asian. Among the HCV subtypes characterized in the Thai samples, subtype 3a was the most predominant (36.4%), followed by 1a (19.9%), 1b (12.6%), 3b (9.7%) and 2a (0.5%). While genotype 1 was prevalent throughout Thailand (27-36%), genotype 3 was more common in the south. Genotype 6 (20.9%) constituted subtype 6f (7.8%), 6n (7.7%), 6i (3.4%), 6j and 6m (0.7% each), 6c (0.3%), 6v and 6xa (0.2% each) and its prevalence was significantly lower in southern Thailand compared to the north and northeast (p = 0.027 and p = 0.030, respectively). Within Southeast Asia, high prevalence of genotype 6 occurred in northern countries such as Myanmar, Laos, and Vietnam, while genotype 3 was prevalent in Thailand and Malaysia. Island nations of Singapore, Indonesia and Philippines demonstrated prevalence of genotype 1. This study further provides regional HCV genotype information that may be useful in fostering sound public health policy and tracking future patterns of HCV spread.
    Matched MeSH terms: Phylogeny
  3. Yong HS, Eamsobhana P, Song SL, Prasartvit A, Lim PE
    Acta Trop, 2015 Aug;148:66-71.
    PMID: 25930187 DOI: 10.1016/j.actatropica.2015.04.020
    Angiostrongylus cantonensis is an important emerging zoonotic parasite causing human eosinophilic meningitis (or meningoencephalitis) in many parts of the world. To-date there is only a single study using mitochondrial cytochrome b (CYTB) gene to determine its genetic structure in eight geographical localities in Thailand. The present study examined the molecular phylogeography of this rat lungworm and its phylogenetic relationship with congeners using CYTB gene marker. A total of 15 CYTB haplotypes was found in 37 sequences from 14 geographical localities (covering north, west, east, central and south regions) in Thailand. These CYTB haplotypes were distinct from those of A. cantonensis for China and Hawaii. In Thailand, some CYTB haplotypes appeared to be confined to specific geographical localities. The partial CYTB DNA nucleotide sequences separated unequivocally the A. cantonensis isolates of Thailand, China and Hawaii as well as the congeners Angiostrongylus malaysiensis, A. costaricensis and Angiostrongylus vasorum, with A. malaysiensis grouped with A. cantonensis and A. costaricensis grouped with A. vasorum. Likewise the congeners of Metastrongylus and Onchocerca genera could also be clearly differentiated. The present study added two new definitive hosts (Bandicota savilei and Rattus losea) and three new localities (Mae Hong Son in the north, Tak in the west, and Phang Nga in the south) for A. malaysiensis in Thailand, indicating its wide occurrence in the country. Three CYTB haplotypes were found in the Thailand samples of A. malaysiensis. In addition to differentiation of congeners, CYTB gene marker could be used for determining the genetic diversity of a given population/taxon.
    Matched MeSH terms: Phylogeny
  4. Yu D, Zhang J, Li P, Zheng R, Shao C
    PLoS One, 2015;10(4):e0124825.
    PMID: 25875761 DOI: 10.1371/journal.pone.0124825
    he Chinese tiger frog Hoplobatrachus rugulosus is widely distributed in southern China, Malaysia, Myanmar, Thailand, and Vietnam. It is listed in Appendix II of CITES as the only Class II nationally-protected frog in China. The bred tiger frog known as the Thailand tiger frog, is also identified as H. rugulosus. Our analysis of the Cyt b gene showed high genetic divergence (13.8%) between wild and bred samples of tiger frog. Unexpected genetic divergence of the complete mt genome (14.0%) was also observed between wild and bred samples of tiger frog. Yet, the nuclear genes (NCX1, Rag1, Rhod, Tyr) showed little divergence between them. Despite this and their very similar morphology, the features of the mitochondrial genome including genetic divergence of other genes, different three-dimensional structures of ND5 proteins, and gene rearrangements indicate that H. rugulosus may be a cryptic species complex. Using Bayesian inference, maximum likelihood, and maximum parsimony analyses, Hoplobatrachus was resolved as a sister clade to Euphlyctis, and H. rugulosus (BT) as a sister clade to H. rugulosus (WT). We suggest that we should prevent Thailand tiger frogs (bred type) from escaping into wild environments lest they produce hybrids with Chinese tiger frogs (wild type).
    Matched MeSH terms: Phylogeny
  5. Ngeow YF, Wong YL, Tan JL, Hong KW, Ng HF, Ong BL, et al.
    PLoS One, 2015;10(4):e0120789.
    PMID: 25830768 DOI: 10.1371/journal.pone.0120789
    Members of the Mycobacterium terrae complex are slow-growing, non-chromogenic acid-fast bacilli found in the natural environment and occasionally in clinical material. These genetically closely-related members are difficult to differentiate by conventional phenotypic and molecular tests. In this paper we describe the use of whole genome data for the identification of four strains genetically similar to Mycobacterium sp. JDM601, a newly identified member of the M. terrae complex. Phylogenetic information from the alignment of genome-wide orthologous genes and single nucleotide polymorphisms show consistent clustering of the four strains together with M. sp. JDM601 into a distinct clade separate from other rapid and slow growing mycobacterial species. More detailed inter-strain comparisons using average nucleotide identity, tetra-nucleotide frequencies and analysis of synteny indicate that our strains are closely related to but not of the same species as M. sp. JDM601. Besides the 16S rRNA signature described previously for the M. terrae complex, five more hypothetical proteins were found that are potentially useful for the rapid identification of mycobacterial species belonging to the M. terrae complex. This paper illustrates the versatile utilization of whole genome data for the delineation of new bacterial species and introduces four new genomospecies to add to current members in the M. terrae complex.
    Matched MeSH terms: Phylogeny
  6. Tan KX, Jacob SA, Chan KG, Lee LH
    Front Microbiol, 2015;6:140.
    PMID: 25798131 DOI: 10.3389/fmicb.2015.00140
    The novel avian influenza A H7N9 virus which caused the first human infection in Shanghai, China; was reported on the 31st of March 2013 before spreading rapidly to other Chinese provinces and municipal cities. This is the first time the low pathogenic avian influenza A virus has caused human infections and deaths; with cases of severe respiratory disease with pneumonia being reported. There were 440 confirmed cases with 122 fatalities by 16 May 2014; with a fatality risk of ∼28%. The median age of patients was 61 years with a male-to-female ratio of 2.4:1. The main source of infection was identified as exposure to poultry and there is so far no definitive evidence of sustained person-to-person transmission. The neuraminidase inhibitors, namely oseltamivir, zanamivir, and peramivir; have shown good efficacy in the management of the novel H7N9 virus. Treatment is recommended for all hospitalized patients, and for confirmed and probable outpatient cases; and should ideally be initiated within 48 h of the onset of illness for the best outcome. Phylogenetic analysis found that the novel H7N9 virus is avian in origin and evolved from multiple reassortments of at least four origins. Indeed the novel H7N9 virus acquired human adaptation via mutations in its eight RNA gene segments. Enhanced surveillance and effective global control are essential to prevent pandemic outbreaks of the novel H7N9 virus.
    Matched MeSH terms: Phylogeny
  7. McMinn P, Lindsay K, Perera D, Chan HM, Chan KP, Cardosa MJ
    J Virol, 2001 Aug;75(16):7732-8.
    PMID: 11462047
    Enterovirus 71 (EV71) is a frequent cause of hand, foot, and mouth disease (HFMD) epidemics associated with severe neurological sequelae in a small proportion of cases. There has been a significant increase in EV71 epidemic activity throughout the Asia-Pacific region since 1997. Recent HFMD epidemics in this region have been associated with a severe form of brainstem encephalitis associated with pulmonary edema and high case fatality rates. In this study, we show that four genetic lineages of EV71 have been prevalent in the Asia-Pacific region since 1997, including two previously undescribed genogroups (B3 and B4). Furthermore, we show that viruses belonging to genogroups B3 and B4 have circulated endemically in Southeast Asia during this period and have been the primary cause of several large HFMD or encephalitis epidemics in Malaysia, Singapore, and Western Australia.
    Matched MeSH terms: Phylogeny
  8. Chua KB, Wang LF, Lam SK, Eaton BT
    Arch Virol, 2002 Jul;147(7):1323-48.
    PMID: 12111411
    A novel paramyxovirus in the genus Rubulavirus, named Tioman virus (TiV), was isolated in 1999 from a number of pooled urine samples of Island Flying Foxes (Pteropus hypomelanus) during the search for the reservoir host of Nipah virus. TiV is antigenically related to Menangle virus (MenV) that was isolated in Australia in 1997 during disease outbreak in pigs. Sequence analysis of the full length genome indicated that TiV is a novel member of the genus Rubulavirus within the subfamily Paramyxovirinae, family Paramyxoviridae. However, there are several features of TiV which make it unique among known paramyxoviruses and rubulaviruses in particular: (1) TiV, like MenV, uses the nucleotide G as a transcriptional initiation site, rather than the A residue used by all other known paramyxoviruses; (2) TiV uses C as the +1 residue for all intergenic regions, a feature not seen for rubulaviruses but common for all other members within the subfamily Paramyxovirinae; (3) Although the attachment protein of TiV has structural features that are conserved in other rubulaviruses, it manifests no overall sequence homology with members of the genus, lacks the sialic acid-binding motif N-R-K-S-C-S and has only two out of the six highly conserved residues known to be important for the catalytic activity of neuraminidase.
    Matched MeSH terms: Phylogeny
  9. Chiang TY, Chiang YC, Chen YJ, Chou CH, Havanond S, Hong TN, et al.
    Mol Ecol, 2001 Nov;10(11):2697-710.
    PMID: 11883883
    Vivipary with precocious seedlings in mangrove plants was thought to be a hindrance to long-range dispersal. To examine the extent of seedling dispersal across oceans, we investigated the phylogeny and genetic structure among East Asiatic populations of Kandelia candel based on organelle DNAs. In total, three, 28 and seven haplotypes of the chloroplast DNA (cpDNA) atpB-rbcL spacer, cpDNA trnL-trnF spacer, and mitochondrial DNA (mtDNA) internal transcribed spacer (ITS) were identified, respectively, from 202 individuals. Three data sets suggested consistent phylogenies recovering two differentiated lineages corresponding to geographical regions, i.e. northern South-China-Sea + East-China-Sea region and southern South-China-Sea region (Sarawak). Phylogenetically, the Sarawak population was closely related to the Ranong population of western Peninsula Malaysia instead of other South-China-Sea populations, indicating its possible origin from the Indian Ocean Rim. No geographical subdivision was detected within the northern geographical region. An analysis of molecular variance (AMOVA) revealed low levels of genetic differentiation between and within mainland and island populations (phiCT = 0.015, phiSC = 0.037), indicating conspicuous long-distance seedling dispersal across oceans. Significant linkage disequilibrium excluded the possibility of recurrent homoplasious mutations as the major force causing phylogenetic discrepancy between mtDNA and the trnL-trnF spacer within the northern region. Instead, relative ages of alleles contributed to non-random chlorotype-mitotype associations and tree inconsistency. Widespread distribution and random associations (chi2 = 0.822, P = 0.189) of eight hypothetical ancestral cytotypes indicated the panmixis of populations of the northern geographical region as a whole. In contrast, rare and recently evolved alleles were restricted to marginal populations, revealing some preferential directional migration.
    Matched MeSH terms: Phylogeny
  10. Wang E, Ni H, Xu R, Barrett AD, Watowich SJ, Gubler DJ, et al.
    J Virol, 2000 Apr;74(7):3227-34.
    PMID: 10708439
    Endemic/epidemic dengue viruses (DEN) that are transmitted among humans by the mosquito vectors Aedes aegypti and Aedes albopictus are hypothesized to have evolved from sylvatic DEN strains that are transmitted among nonhuman primates in West Africa and Malaysia by other Aedes mosquitoes. We tested this hypothesis with phylogenetic studies using envelope protein gene sequences of both endemic/epidemic and sylvatic strains. The basal position of sylvatic lineages of DEN-1, -2, and -4 suggested that the endemic/epidemic lineages of these three DEN serotypes evolved independently from sylvatic progenitors. Time estimates for evolution of the endemic/epidemic forms ranged from 100 to 1,500 years ago, and the evolution of endemic/epidemic forms represents relatively recent events in the history of DEN evolution. Analysis of envelope protein amino acid changes predicted to have accompanied endemic/epidemic emergence suggested a role for domain III in adaptation to new mosquito and/or human hosts.
    Matched MeSH terms: Phylogeny
  11. Le TH, Blair D, McManus DP
    Ann Trop Med Parasitol, 2002 Mar;96(2):155-64.
    PMID: 12080976
    Recent electrophoretic data have indicated that Schistosoma japonicum in mainland China may be a species complex, with the existence of a cryptic species being predicted from the analysis of schistosome populations from Sichuan province. To investigate the Sichuan form of S. japonicum, 4.9 kbp of mitochondrial DNA from each of three samples of the parasite from China (two from Sichuan and one from Hunan) and one from Sorsogon in the Philippines were amplified, sequenced and characterized. The sequence data were compared with those from the related South-east Asian species of S. mekongi (Khong Island, Laos) and S. mlayensis (Baling, Malaysia) and that from S. japonicm from Anhui (China). At both the nucleotide and amino-acid levels, the variation among the five S. japonicum samples was limited (< 1%). This was consistent with the conclusions drawn from previous molecular studies, in which minimal variation among S. japonicum populations was also detected. In contrast, S. mekongi and S. malayensis, species recognized as separate but closely related, differ from each other by about 10%, and each differs by 25%-26% from S. japonicum. Phylogenetic trees provided a graphic representation of these differences, showing all S. japonicum sequences to be very tightly clustered and distant from S. mekongi and S. malayensis, the last two being clearly distinct from each other. The results thus indicate no significant intra-specific genetic variation among S. japonicum samples collected from different geographical areas and do not support the idea of a distinct form in Sichuan.
    Matched MeSH terms: Phylogeny
  12. Teo CH, Tan SH, Othman YR, Schwarzacher T
    J. Biochem. Mol. Biol. Biophys., 2002 Jun;6(3):193-201.
    PMID: 12186754
    Ty1-copia-like retrotransposons have been identified and investigated in several plant species. Here, the internal region of the reverse transcriptase (RT) gene of Ty1-copia-like retrotransposons was amplified by PCR from total genomic DNA of 10 varieties of banana. Two to four clones from each variety were sequenced. Extreme heterogeneity in the sequences of Ty1-copia-like retrotransposons from all the varieties was revealed following sequence analysis of the reverse transcriptase (RT) fragments. The size of the individual RT gene fragments varied between 213 and 309 bp. Southern blots of genomic DNA digested from Musa acuminata and other banana varieties probed with W8 clone from M. acuminata and A4 clone from Pisang Abu Nipah showed similar strong, multiple restriction fragments together with other faint hybridization band patterns with variable intensities indicating the presence of many copies of the Ty1-copia-like retrotransposons in the genomes. There was no correlation between retroelement sequence and the banana species (with A or B genomes) from which it arose, suggesting that the probes are not useful for tracking genomes through breeding populations.
    Matched MeSH terms: Phylogeny
  13. Hall RA, Scherret JH, Mackenzie JS
    Ann N Y Acad Sci, 2001 Dec;951:153-60.
    PMID: 11797773
    Kunjin (KUN) is a flavivirus in the Japanese encephalitis antigenic complex that was first isolated from Culex annulirostris mosquitoes captured in northern Australia in 1960. It is the etiological agent of a human disease characterized by febrile illness with rash or mild encephalitis and, occasionally, of a neurological disease in horses. KUN virus shares a similar epidemiology and ecology with the closely related Murray Valley encephalitis (MVE) virus, the major causative agent of arboviral encephalitis in Australia. Based on traditional antigenic methods, KUN was initially found to be similar to, but distinct from, reference strains of West Nile (WN) virus and designated as a new species. However, more recent phylogenic analyses have revealed that some strains of WN virus, including the isolates from New York, are more similar to KUN virus and form a separate lineage to other WN viruses. An unusual KUN isolate from Malaysia and the African virus Koutango appear to form additional lineages within the WN group of viruses. While these findings are in agreement with the Seventh Report of the International Committee for the Taxonomy of Viruses that designates KUN as a subtype of West Nile, they also suggest that the species should be further subdivided into additional subtypes.
    Matched MeSH terms: Phylogeny
  14. AbuBakar S, Chan YF, Lam SK
    N Engl J Med, 2000 Feb 3;342(5):355-6.
    PMID: 10660400 DOI: 10.1056/NEJM200002033420513
    Matched MeSH terms: Phylogeny
  15. Muthuchelvan D, Venkataramanan R, Hemadri D, Sanyal A, Tosh C
    Acta Virol., 2001 Jun;45(3):159-67.
    PMID: 11774894
    Partial nucleotide sequences of 1D gene of 38 isolates of foot-and-mouth disease virus (FMDV) of serotypes O, A and Asia 1 originating from various parts of India were determined. Field materials were subjected straight to RNA extraction, reverse transcription - PCR (RT-PCR) and sequencing. Also 3 FMDV vaccine strains, IND R2/75 (serotype O), IND 63/72 (serotype Asia 1) and IND 17/77 (serotype A) were included in the analysis. The seqences were compared mutually as well as with available corresponding sequences of other FMDV isolates, and their phylogenetic relationships were calculated. The deduced amino acid sequences showed that the serotype O isolates were relatively conserved as compared to serotype Asia 1 or A isolates from India. In phylogenetic analysis, the serotype O viruses clustered in two genotypes, one including the European vaccine strain (O1/K) and the other represented by the isolates from Bangladesh, India, Nepal and Turkey. The serotype Asia 1 viruses clustered in two groups of single genotype where the prototype strain from Pakistan (PAK 1/54) formed one group and the other was formed by the isolates from Bangladesh, Bhutan, India, Israel and Nepal. In serotype A viruses three well-differentiated genotypes were observed. The isolates from Azerbaijan, Bangladesh, Malaysia and India formed the first genotype. The second genotype was formed by isolates from Iran, Saudi Arabia and Turkey, while two recent Iranian isolates represented the third genotype. In India, the prevalence of at least one genotype could be identified in each serotype. This evolutionary clustering of isolates from the neighbor countries is not surprising, since these countries share border with India. The genetic relatedness between sequences of isolates from India and those from distant places is indicative of spread of the virus between the countries. Of importance is the fact that clinical materials proved useful for rapid generation of sequences and subsequent studying of molecular epidemiology of the disease.
    Matched MeSH terms: Phylogeny
  16. Gibbs AJ, Mackenzie AM, Abdul-Samad N
    Arch Virol, 1997;142(8):1697-702.
    PMID: 9672629
    A tymoyirus isolated from Malaysian crops of Calopogonium mucunoides has been shown to have virions that are serologically indistinguishable from those of clitoria yellow vein tymovirus. We have sequenced the virion protein (VP) gene of the virus and have found that although it is a member of the cluster that includes CYVV, it is the most distinct member of that cluster (< 62% sequence identity with all the others), and is clearly a separate species, which we propose should be named calopogonium yellow vein virus. Most of the serological specificity of the virions of tymoviruses seems to reside in the C-terminal hexapeptide of the virion protein.
    Matched MeSH terms: Phylogeny
  17. Guo J, Kitamura T, Ebihara H, Sugimoto C, Kunitake T, Takehisa J, et al.
    J Gen Virol, 1996 May;77 ( Pt 5):919-27.
    PMID: 8609488
    The JC polyomavirus (JCV) is ubiquitous in humans infecting children asymptomatically, then persisting in renal tissue. Since JCV DNA can be readily isolated from urine, it should be a useful tool with which to study the evolution of DNA viruses in humans. We showed that JCV DNA from the urine of Japanese, Taiwanese, Dutch and German patients can be classified into A and B types, based upon restriction fragment length polymorphisms (RFLPs). This work was extended in the present study. We established multiple JCV DNA clones from the UK, Spain, Italy, Sweden, South Korea, People's Republic of China, Malaysia, Indonesia, Mongolia, India, Sri Lanka, Saudi Arabia, Ethiopia, Kenya, Zambia, South Africa and Ghana. Using type-specific RFLPs, most clones except the four clones from Ghana were classified as either type A or B. We constructed a molecular phylogenetic tree for the Ghanaian clones and several representative type A and B clones. According to the phylogenetic tree, the Ghanaian clones constituted a major new group, tentatively named type C. From the findings presented here and elsewhere, the following conclusions were drawn: (i) type A is prevalent only in Europe; (ii) type B is found mainly in Asia and Africa; and (iii) type C is localized to part of Africa. Our findings should help to clarify how JCV evolved in humans.
    Matched MeSH terms: Phylogeny
  18. Chen WR, Tesh RB, Rico-Hesse R
    J Gen Virol, 1990 Dec;71 ( Pt 12):2915-22.
    PMID: 2273391
    Forty-six strains of Japanese encephalitis (JE) virus from a variety of geographic areas in Asia were examined by primer-extension sequencing of the RNA template. A 240 nucleotide sequence from the pre-M gene region was selected for study because it provided sufficient information for determining genetic relationships among the virus isolates. Using 12% divergence as a cutoff point for virus relationships, the 46 isolates fell into three distinct genotypic groups. One genotypic group consisted of JE virus isolates from northern Thailand and Cambodia. A second group was composed of isolates from southern Thailand, Malaysia, Sarawak and Indonesia. The remainder of the isolates, from Japan, China, Taiwan, the Philippines, Sri Lanka, India and Nepal, made up a third group. The implications of these findings in relation to the epidemiology of JE are discussed. Results of this study demonstrate that the comparison of short nucleotide sequences can provide insight into JE virus evolution, transmission and, possibly, pathogenesis.
    Matched MeSH terms: Phylogeny
  19. Perera D, Podin Y, Akin W, Tan CS, Cardosa MJ
    BMC Infect Dis, 2004 May 4;4:11.
    PMID: 15122971
    Human enterovirus 71 has emerged as an important pathogen in the Asia Pacific region and it is important to be able to make a rapid and specific diagnosis for outbreak control. Recent Asian strains of Coxsackievirus A16 have changes in the VP1 gene which causes mispriming of widely used primers for human enterovirus 71 specific identification.
    Matched MeSH terms: Phylogeny
  20. Chowdhury SM, Omar AR, Aini I, Hair-Bejo M, Jamaluddin AA, Md-Zain BM, et al.
    Arch Virol, 2003 Dec;148(12):2437-48.
    PMID: 14648297
    Specific-pathogen-free (SPF) chickens inoculated with low passage Chicken anaemia virus (CAV), SMSC-1 and 3-1 isolates produced lesions suggestive of CAV infection. Repeated passages of the isolates in cell culture until passage 60 (P60) and passage 123 produced viruses that showed a significantly reduced level of pathogenicity in SPF chickens compared to the low passage isolates. Sequence comparison indicated that nucleotide changes in only the coding region of the P60 passage isolates were thought to contribute to virus attenuation. Phylogenetic analysis indicated that SMSC-1 and 3-1 were highly divergent, but their P60 passage derivatives shared significant homology to a Japanese isolate A2.
    Matched MeSH terms: Phylogeny
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links