1
|
Castelli G, Bruno F, Caputo V, Fiorella S, Sammarco I, Lupo T, Migliazzo A, Vitale F, Reale S. Genetic tools discriminate strains of Leishmania infantum isolated from humans and dogs in Sicily, Italy. PLoS Negl Trop Dis 2020; 14:e0008465. [PMID: 32706789 PMCID: PMC7406075 DOI: 10.1371/journal.pntd.0008465] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 08/05/2020] [Accepted: 06/09/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Leishmaniasis is one of the most important vector-borne diseases and it represents a serious world health problem affecting millions of people. High levels of Leishmania infections, affecting both humans and animals, are recognized among Italian regions. Among these, Sicily has one of the highest prevalence of Leishmania infection. METHODOLOGY/PRINCIPAL FINDINGS Seventy-eight Leishmania strains isolated from human and animal samples across Sicily, were analyzed for the polymorphic k26-gene and genotypes were assigned according to the size of the PCR products. A multilocus microsatellite typing (MLMT) approach based on the analysis of 11 independent loci was used to investigate populations structure and genetic diversity of the isolated strains. Six L. infantum reference strains were included in the analysis for comparison. Bayesian clustering analysis of microsatellite data showed that all the isolated strains clustered in two genetically distinct populations, corresponding to human and canine isolates respectively. A further subdivision was observed between the two main groups, giving a good correlation between human strains and their geographic origin, conversely canine population showed a great genetic variability diffused in the territory. CONCLUSIONS/SIGNIFICANCE Among the 78 Leishmania isolates, K26 analysis detected 71 samples (91%) as MON-1 zymodeme, confirming it as the predominant strain in Mediterranean area and 7 human samples (9%) as non-MON-1. MLMT gives important insights into the epidemiology of leishmaniases and allows characterization of different strains to a higher resolution than possible with zymodeme typing. Two main populations presented a strong correlation respect to the different hosts, exhibiting a co-circulation of two distinct populations of L. infantum. The population found in infected humans exhibited a correlation with geographic origin. These clusters could represent a geographically restricted population of strains with the same or related genotypes. This study can contribute to an understanding of Leishmania epidemiology, including the spread of reservoirs and sand fly vectors in the different foci of infection, characterizing parasites within the different hosts.
Collapse
Affiliation(s)
- Germano Castelli
- National Reference Center for Leishmaniasis (C.Re.Na.L.), Istituto Zooprofilattico Sperimentale della Sicilia, Palermo, Italy
| | - Federica Bruno
- National Reference Center for Leishmaniasis (C.Re.Na.L.), Istituto Zooprofilattico Sperimentale della Sicilia, Palermo, Italy
| | - Valentina Caputo
- Section of Dermatology, Department of Health Promotion, Maternal-Infant, Internal Medicine and Specialization of Excellence “G. D’Alessandro” (PROMISE) University of Palermo, Palermo, Italy.
| | - Santi Fiorella
- Section of Dermatology, Department of Health Promotion, Maternal-Infant, Internal Medicine and Specialization of Excellence “G. D’Alessandro” (PROMISE) University of Palermo, Palermo, Italy.
| | - Ignazio Sammarco
- Tecnologie Diagnostiche Innovative, Istituto Zooprofilattico Sperimentale della Sicilia, Palermo, Italy
| | - Tiziana Lupo
- Tecnologie Diagnostiche Innovative, Istituto Zooprofilattico Sperimentale della Sicilia, Palermo, Italy
| | - Antonella Migliazzo
- National Reference Center for Leishmaniasis (C.Re.Na.L.), Istituto Zooprofilattico Sperimentale della Sicilia, Palermo, Italy
| | - Fabrizio Vitale
- National Reference Center for Leishmaniasis (C.Re.Na.L.), Istituto Zooprofilattico Sperimentale della Sicilia, Palermo, Italy
- * E-mail:
| | - Stefano Reale
- Tecnologie Diagnostiche Innovative, Istituto Zooprofilattico Sperimentale della Sicilia, Palermo, Italy
| |
Collapse
|
2
|
Mladineo I, Trumbić Ž, Radonić I, Vrbatović A, Hrabar J, Bušelić I. Anisakis simplex complex: ecological significance of recombinant genotypes in an allopatric area of the Adriatic Sea inferred by genome-derived simple sequence repeats. Int J Parasitol 2017; 47:215-223. [DOI: 10.1016/j.ijpara.2016.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/18/2016] [Accepted: 11/20/2016] [Indexed: 11/24/2022]
|
3
|
Genome-wide discovery and development of polymorphic microsatellites from Leishmania panamensis parasites circulating in central Panama. Parasit Vectors 2015; 8:527. [PMID: 26459121 PMCID: PMC4603350 DOI: 10.1186/s13071-015-1153-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 10/08/2015] [Indexed: 12/01/2022] Open
Abstract
Background The parasite Leishmania panamensis is the main cause of leishmaniasis in Panama. The disease is largely uncontrolled, with a rising incidence and no appropriate control measures. While microsatellites are considered some of the best genetic markers to study population genetics and molecular epidemiology in these and other parasites, none has been developed for L. panamensis. Findings Here we have developed and tested a new panel of microsatellites for this species, based on high-throughput genome-wide screening. The new set of microsatellites is composed of seventeen loci, mainly spanning trinucleotide or longer motifs. We have evaluated the sensitivity and specificity of the panel based on a sample of 27 isolates obtained from cutaneous leishmaniasis patients from central Panama and also several reference species from both L. (Leishmania) and L. (Viannia) subgenera. The genetic equilibrium was assessed both intra- and inter-loci, while the reproductive mode was evaluated using several tests. The new SSR panel shows high polymorphism and sensitivity, as well as good specificity. The preliminary data described here for L. panamensis suggest extensive departure from Hardy-Weinberg proportions, significant linkage disequilibrium and strong deficit of heterozygotes. Several recombination tests involving multilocus linkage disequilibrium and a phylogenetic approach allowed rejection of frequent recombination in our dataset. Conclusions The genome-wide strategy described here proved to be useful to identify and test new polymorphic SSR loci in Leishmania. The new panel of polymorphic microsatellites is a valuable contribution to the existing molecular markers for the study of genetic structure and other aspects of this important species. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1153-2) contains supplementary material, which is available to authorized users.
Collapse
|
4
|
The Genetic Relationship between Leishmania aethiopica and Leishmania tropica Revealed by Comparing Microsatellite Profiles. PLoS One 2015. [PMID: 26196393 PMCID: PMC4511230 DOI: 10.1371/journal.pone.0131227] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Leishmania (Leishmania) aethiopica and L. (L.) tropica cause cutaneous leishmaniases and appear to be related. L. aethiopica is geographically restricted to Ethiopia and Kenya; L. tropica is widely dispersed from the Eastern Mediterranean, through the Middle East into eastern India and in north, east and south Africa. Their phylogenetic inter-relationship is only partially revealed. Some studies indicate a close relationship. Here, eight strains of L. aethiopica were characterized genetically and compared with 156 strains of L. tropica from most of the latter species' geographical range to discern the closeness. METHODOLOGY/PRINCIPAL FINDINGS Twelve unlinked microsatellite markers previously used to genotype strains of L. tropica were successfully applied to the eight strains of L. aethiopica and their microsatellite profiles were compared to those of 156 strains of L. tropica from various geographical locations that were isolated from human cases of cutaneous and visceral leishmaniasis, hyraxes and sand fly vectors. All the microsatellite profiles were subjected to various analytical algorithms: Bayesian statistics, distance-based and factorial correspondence analysis, revealing: (i) the species L. aethiopica, though geographically restricted, is genetically very heterogeneous; (ii) the strains of L. aethiopica formed a distinct genetic cluster; and (iii) strains of L. aethiopica are closely related to strains of L. tropica and more so to the African ones, although, by factorial correspondence analysis, clearly separate from them. CONCLUSIONS/SIGNIFICANCE The successful application of the 12 microsatellite markers, originally considered species-specific for the species L. tropica, to strains of L. aethiopica confirmed the close relationship between these two species. The Bayesian and distance-based methods clustered the strains of L. aethiopica among African strains of L. tropica, while the factorial correspondence analysis indicated a clear separation between the two species. There was no correlation between microsatellite profiles of the eight strains of L. aethiopica and the type of leishmaniasis, localized (LCL) versus diffuse cutaneous leishmaniasis (DCL), displayed by the human cases.
Collapse
|
5
|
Aluru S, Hide M, Michel G, Bañuls AL, Marty P, Pomares C. Multilocus microsatellite typing of Leishmania and clinical applications: a review. ACTA ACUST UNITED AC 2015; 22:16. [PMID: 25950900 PMCID: PMC4423940 DOI: 10.1051/parasite/2015016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 04/17/2015] [Indexed: 12/03/2022]
Abstract
Microsatellite markers have been used for Leishmania genetic studies worldwide, giving useful insight into leishmaniasis epidemiology. Understanding the geographic distribution, dynamics of Leishmania populations, and disease epidemiology improved markedly with this tool. In endemic foci, the origins of antimony-resistant strains and multidrug treatment failures were explored with multilocus microsatellite typing (MLMT). High genetic variability was detected but no association between parasite genotypes and drug resistance was established. An association between MLMT profiles and clinical disease manifestations was highlighted in only three studies and this data needs further confirmation. At the individual level, MLMT provided information on relapse and reinfection when multiple leishmaniasis episodes occurred. This information could improve knowledge of epidemiology and guide therapeutic choices for active chronic visceral leishmaniasis, the disease form in some HIV-positive patients.
Collapse
Affiliation(s)
- Srikanth Aluru
- Aix-Marseille Université, Marseille, France - INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Toxines Microbiennes dans la Relation Hôte Pathogènes, 06204 Nice Cedex 3, France
| | - Mallorie Hide
- UMR MIVEGEC IRD 224-CNRS 5290, Universités Montpellier 1 et 2, Montpellier, France
| | - Gregory Michel
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Toxines Microbiennes dans la Relation Hôte Pathogènes, 06204 Nice Cedex 3, France - Université de Nice Sophia Antipolis, Faculté de Médecine, 06107 Nice Cedex 2, France
| | - Anne-Laure Bañuls
- UMR MIVEGEC IRD 224-CNRS 5290, Universités Montpellier 1 et 2, Montpellier, France
| | - Pierre Marty
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Toxines Microbiennes dans la Relation Hôte Pathogènes, 06204 Nice Cedex 3, France - Université de Nice Sophia Antipolis, Faculté de Médecine, 06107 Nice Cedex 2, France - Parasitologie-Mycologie, Centre Hospitalier Universitaire l'Archet, CS 23079, 06202 Nice Cedex 3, France
| | - Christelle Pomares
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Toxines Microbiennes dans la Relation Hôte Pathogènes, 06204 Nice Cedex 3, France - Université de Nice Sophia Antipolis, Faculté de Médecine, 06107 Nice Cedex 2, France - Parasitologie-Mycologie, Centre Hospitalier Universitaire l'Archet, CS 23079, 06202 Nice Cedex 3, France
| |
Collapse
|
6
|
Najafzadeh N, Sedaghat MM, Sultan SS, Spotin A, Zamani A, Taslimian R, Yaghoubinezhad A, Parvizi P. The existence of only one haplotype of Leishmania major in the main and potential reservoir hosts of zoonotic cutaneous leishmaniasis using different molecular markers in a focal area in Iran. Rev Soc Bras Med Trop 2014; 47:599-606. [DOI: 10.1590/0037-8682-0164-2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 10/04/2014] [Indexed: 11/22/2022] Open
Affiliation(s)
| | | | | | - Adel Spotin
- Pasteur Institute of Iran, Iran; Tabriz University, Medical Sciences, Iran
| | | | | | - Amir Yaghoubinezhad
- Pasteur Institute of Iran, Iran; Higher Education Institute of Rab-Rashid, Iran
| | | |
Collapse
|
7
|
Dikhit MR, Moharana KC, Sahoo BR, Sahoo GC, Das P. LeishMicrosatDB: open source database of repeat sequences detected in six fully sequenced Leishmania genomes. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2014; 2014:bau078. [PMID: 25125444 PMCID: PMC4132413 DOI: 10.1093/database/bau078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
UNLABELLED A Leishmania Microsatellite Database (LeishMicrosatDB) is reported for genome wise mining of microsatellites in six Leishmania species, using in silico techniques. This was created to provide parasitologists a platform to understand the genome characterization, mapping, phylogeny and evolutionary analysis. The present version of the database contains 1,738,669 simple sequence repeats of which 181 s756 repeats are present in compound form. The repeats can be sought in a chromosome using input parameters such as repeat type (mono- hexa), coding status, repeat unit length and repeat sequence motif. The genic repeats have been further hyperlinked with their corresponding locus id, and the database is appended with primer3 plus for primer designing of selected repeats with left and right flanking sequences up to 250 bp. Information on clustering and polymorphic repeats can also be retrieved. This database may also be adopted as a tool to study the relative occurrence and distribution of microsatellites across the parasitic genome. The database can enable a biologist to select markers at desired intervals over the chromosomes, and can be accessed as an open source repository at http://biomedinformri.com/leishmicrosat. DATABASE URL http://biomedinformri.com/leishmicrosat.
Collapse
Affiliation(s)
- Manas R Dikhit
- Biomedical Informatics Center and Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences, Patna 800007, India
| | - Kanhu C Moharana
- Biomedical Informatics Center and Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences, Patna 800007, India
| | - Bikash R Sahoo
- Biomedical Informatics Center and Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences, Patna 800007, India
| | - Ganesh C Sahoo
- Biomedical Informatics Center and Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences, Patna 800007, India
| | - Pradeep Das
- Biomedical Informatics Center and Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences, Patna 800007, IndiaBiomedical Informatics Center and Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences, Patna 800007, India
| |
Collapse
|
8
|
Mahnaz T, Al-Jawabreh A, Kuhls K, Schönian G. Multilocus microsatellite typing shows three different genetic clusters of Leishmania major in Iran. Microbes Infect 2011; 13:937-42. [PMID: 21664984 DOI: 10.1016/j.micinf.2011.05.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 05/13/2011] [Accepted: 05/13/2011] [Indexed: 11/18/2022]
Abstract
Ten polymorphic microsatellite markers were used to analyse 25 strains of Leishmania major collected from cutaneous leishmaniasis cases in different endemic areas in Iran. Nine of the markers were polymorphic, revealing 21 different genotypes. The data displayed significant microsatellite polymorphism with rare allelic heterozygosity. Bayesian statistic and distance based analyses identified three genetic clusters among the 25 strains analysed. Cluster I represented mainly strains isolated in the west and south-west of Iran, with the exception of four strains originating from central Iran. Cluster II comprised strains from the central part of Iran, and cluster III included only strains from north Iran. The geographical distribution of L. major in Iran was supported by comparing the microsatellite profiles of the 25 Iranian strains to those of 105 strains collected in 19 Asian and African countries. The Iranian clusters I and II were separated from three previously described populations comprising strains from Africa, the Middle East and Central Asia whereas cluster III grouped together with the Central Asian population. The considerable genetic variability of L. major might be related to the existence of different populations of Phlebotomus papatasi and/or to differences in reservoir host abundance in different parts of Iran.
Collapse
Affiliation(s)
- Tashakori Mahnaz
- Ali-Ebne Abitaleb Hospital, Rafsanjan University of Medical Sciences, Rafsanjan, Iran
| | | | | | | |
Collapse
|
9
|
Molecular approaches for a better understanding of the epidemiology and population genetics ofLeishmania. Parasitology 2010; 138:405-25. [DOI: 10.1017/s0031182010001538] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
SUMMARYMolecular approaches are being used increasingly for epidemiological studies of visceral and cutaneous leishmaniases. Several molecular markers resolving genetic differences betweenLeishmaniaparasites at species and strain levels have been developed to address key epidemiological and population genetic questions. The current gold standard, multilocus enzyme typing (MLEE), needs cultured parasites and lacks discriminatory power. PCR assays identifying species directly with clinical samples have proven useful in numerous field studies. Multilocus sequence typing (MLST) is potentially the most powerful phylogenetic approach and will, most probably, replace MLEE in the future. Multilocus microsatellite typing (MLMT) is able to discriminate below the zymodeme level and seems to be the best candidate for becoming the gold standard for distinction of strains. Population genetic studies by MLMT revealed geographical and hierarchic population structure inL. tropica, L. majorand theL. donovanicomplex. The existence of hybrids and gene flow betweenLeishmaniapopulations suggests that sexual recombination is more frequent than previously thought. However, typing and analytical tools need to be further improved. Accessible databases should be created and sustained for integrating data obtained by different researchers. This would allow for global analyses and help to avoid biases in analyses due to small sample sizes.
Collapse
|
10
|
An integrated pipeline for the development of novel panels of mapped microsatellite markers for Leishmania donovani complex, Leishmania braziliensis and Leishmania major. Parasitology 2008; 135:567-74. [PMID: 18371241 DOI: 10.1017/s0031182008004186] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A panel of microsatellites mapped to the Leishmania genome might make it possible to find associations between specific loci and phenotypic traits. To identify such loci, a Perl programme was written that scans the sequence of a genome and writes all loci containing microsatellites to a MySQL database. The programme was applied to the sequences of the L. braziliensis, L. infantum and L. major genomes. The database is publicly available over the internet: http://www.genomics.liv.ac.uk/tryps/resources.html 'Microsatellite Locus Extractor', and allows the selection of mapped microsatellites that meet user-defined criteria from a specified region of the selected genome. The website also incorporates a primer design pipeline that will design primers to amplify the selected loci. Using this pipeline 12 out of 17 primer sets designed against the L. infantum genome generated polymorphic PCR products. A tailed primer protocol was used to label all microsatellite primers with a single set of labelled primers. To avoid the culture of parasites prior to genotyping, sets of nested PCR primers were developed to amplify parasite DNA eluted from microscope slides. The limit of detection was approximately 1.6 parasite equivalents. However, only 6/56 DNA from slides stored at ambient temperature for over 6 months gave positive PCR results.
Collapse
|
11
|
Ochsenreither S, Kuhls K, Schaar M, Presber W, Schönian G. Multilocus microsatellite typing as a new tool for discrimination of Leishmania infantum MON-1 strains. J Clin Microbiol 2006; 44:495-503. [PMID: 16455904 PMCID: PMC1392658 DOI: 10.1128/jcm.44.2.495-503.2006] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Leishmania donovani complex, which consists of L. donovani, L. infantum-L. chagasi, and L. archibaldi, is responsible for visceral manifestations of leishmaniasis. Multilocus enzyme electrophoresis is the standard method for the characterization and identification of strains of Leishmania. For L. infantum, the predominance of zymodeme MON-1 significantly reduces the discriminative power of this approach. In the present study, we developed 17 independent polymorphic microsatellite markers for the typing of strains of L. infantum, with the main emphasis on zymodeme MON-1. The discriminative powers of 11 markers selected from among these markers were tested by using a panel of 63 isolates of the L. donovani complex. Unique multilocus genotypes were observed for the strains analyzed, with only three exceptions. Model-based and distance-based analyses of the data set showed comparable results. It was possible to discriminate between L. donovani sensu stricto, a non-MON-1 group of L. infantum isolates, and a MON-1 group of L. infantum isolates. Within MON-1, three clusters with geographical correlations became apparent. The frequency of heterozygosity in the alleles analyzed varied extremely between the different groups of isolates. The main clusters described are not consistent with species definitions based on isoenzyme analysis but confirm the results of former PCR-based investigations.
Collapse
Affiliation(s)
- Sebastian Ochsenreither
- Institute of Microbiology and Hygiene, Charité Universitätsmedizin Berlin, Dorotheenstr. 96, 10117 Berlin, Germany
| | | | | | | | | |
Collapse
|
12
|
Elfari M, Schnur LF, Strelkova MV, Eisenberger CL, Jacobson RL, Greenblatt CL, Presber W, Schönian G. Genetic and biological diversity among populations of Leishmania major from Central Asia, the Middle East and Africa. Microbes Infect 2005; 7:93-103. [PMID: 15716069 DOI: 10.1016/j.micinf.2004.09.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2004] [Revised: 09/15/2004] [Accepted: 09/16/2004] [Indexed: 11/15/2022]
Abstract
Evidence is provided for genetic and biological variation among Leishmania major strains that correlates with their geographical origin. The host-parasite relationship also appears to be specific. Great gerbils, Rhombomys opimus, and fat sand rats, Psammomys obesus, are the main reservoir hosts in Central Asia and the Middle East, respectively. However, the Central Asian parasite failed to infect the Middle Eastern rodent host in the laboratory, and vice versa. A permissively primed intergenic polymorphic (PPIP)-PCR and a single-stranded conformation polymorphism (SSCP)-PCR exposed genetic polymorphism among 30 strains of L. major from different geographical regions. This was verified by subsequent sequencing of DNA from the same strains using four genomic targets: (a) the NADH-dehydrogenase (NADH-DH) gene, (b) the 6-phosphogluconate dehydrogenase (6PGD) gene, (c) the ribosomal internal transcribed spacers, and (d) an anonymous DNA sequence originally amplified with random primers. All the genetic markers indicated that the nine Central Asian strains were a separate homogenous genetic group. The Middle Eastern strains formed another geographical group that displayed heterogeneity corresponding with their different Middle Eastern locations. Molecular markers and host-parasite relationships confirmed that Central Asian and Middle Eastern strains are genetically and biologically distinct sub-populations of L. major. Three African strains of L. major were genetically closer to the Middle Eastern strains, and a representative one did infect fat sand rats, but they had distinct permissively primed inter-genic polymorphic PCR patterns and internal transcribed spacer 2 types.
Collapse
Affiliation(s)
- Mustafa Elfari
- Department of Parasitology, Institute of Microbiology and Hygiene, Charité University Medicine Berlin, Dorotheenstr. 96, D-10098 Berlin, Germany
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Wickstead B, Ersfeld K, Gull K. Repetitive elements in genomes of parasitic protozoa. Microbiol Mol Biol Rev 2003; 67:360-75, table of contents. [PMID: 12966140 PMCID: PMC193867 DOI: 10.1128/mmbr.67.3.360-375.2003] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Repetitive DNA elements have been a part of the genomic fauna of eukaryotes perhaps since their very beginnings. Millions of years of coevolution have given repeats central roles in chromosome maintenance and genetic modulation. Here we review the genomes of parasitic protozoa in the context of the current understanding of repetitive elements. Particular reference is made to repeats in five medically important species with ongoing or completed genome sequencing projects: Plasmodium falciparum, Leishmania major, Trypanosoma brucei, Trypanosoma cruzi, and Giardia lamblia. These organisms are used to illustrate five thematic classes of repeats with different structures and genomic locations. We discuss how these repeat classes may interact with parasitic life-style and also how they can be used as experimental tools. The story which emerges is one of opportunism and upheaval which have been employed to add genetic diversity and genomic flexibility.
Collapse
Affiliation(s)
- Bill Wickstead
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | | | | |
Collapse
|
14
|
Jamjoom MB, Ashford RW, Bates PA, Kemp SJ, Noyes HA. Towards a standard battery of microsatellite markers for the analysis of the Leishmania donovani complex. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2002; 96:265-70. [PMID: 12061973 DOI: 10.1179/000349802125000790] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The investigation of microsatellite markers has recently superseded that of isoenzymes for many population-biology applications. Microsatellites have the advantages of being dominant, neutral, highly polymorphic and easily scored by high-throughput methods. However, it is necessary to develop a new panel of markers for each group of organisms of interest. Previously, only about 5% of the markers that amplify Leishmania major microsatellite loci were also found to amplify L. donovani loci. A panel of 20 microsatellite markers that are polymorphic in L. donovani and L. infantum has now been developed, using a rapid-enrichment method that will be suitable for developing libraries of markers for other trypanosomatid species. This is the first panel of polymorphic microsatellite markers, to be isolated de novo from any species of Leishmania, that is large enough for population-biology applications.
Collapse
Affiliation(s)
- M B Jamjoom
- Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, UK
| | | | | | | | | |
Collapse
|