Characterization of Oesophagostomum asperum and O. columbianum by internal transcribed spacers of nuclear ribosomal DNA

2012 ◽  
Vol 88 (1) ◽  
pp. 74-81 ◽  
Author(s):  
G.H. Zhao ◽  
B. Hu ◽  
J.K. Song ◽  
Y.Q. Jia ◽  
H.M. Li ◽  
...  

AbstractIn the present study, the internal transcribed spacers (ITS) of ribosomal DNA (rDNA) of Oesophagostomum asperum and O. columbianum were amplified and sequenced. The ITS-1, 5.8S and ITS-2 rDNA sequences of O. asperum were 374 bp, 153 bp and 259 bp in length, respectively, and the corresponding sequences of O. columbianum were 259, 153 and 218 bp in length, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA between the two Oesophagostomum species were 9.5–10.2% and 12.7–13.9%, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA among members of the genus Oesophagostomum were 2.5–11.6% and 6.8–22.3%, respectively. Based on genetic markers in the ITS rDNA, an effective polymerase chain reaction (PCR) approach was developed to differentiate O. columbianum from O. asperum with a sensitivity of 0.2 ng/μl DNA. Since accurate characterization of parasites at different taxonomic levels is essential for population genetic studies and control of parasitosis, the present findings have important implications for studying epidemiology, taxonomy and population biology, as well as for the control of oesophagostomiasis.

2020 ◽  
Vol 16 (2) ◽  
pp. 135-150
Author(s):  
Amjed Qays Alqaisi ◽  
◽  
Harith Saeed Al-Warid ◽  
Azhar A. Al-Moussawi ◽  
◽  
...  

Contracaecum rudolphii Hartwich, 1964 is a nematode which causes major concerns to human and wildlife animal’s health. However, the population genetics of C. rudolphii has been poorly studied in Iraq. In order to gain a deeper understanding in the outline of the genetic diversity of the nematode C. rudolphii that were isolated from its host cormorant Phalacrocorax carbo (Linnaeus, 1758), in the middle areas of Iraq, twenty specimens of C. rudolphii adults were isolated from nine individuals of P. carbo. The first (ITS-1) internal transcribed spacers (ITS) of ribosomal DNA (rDNA) of C. rudolphii were amplified using conventional polymerase chain reaction (PCR); then, the amplicons were subjected to sequencing. Concatenation of ITS-1 (rDNA) sequences resulted in four unique genotypes that have not been previously recorded in Iraq. The present study showed that the most common genotype occurred in 85% of C. rudolphii, and in 88.9% of cormorants. Furthermore, the infrapopulation difference in the genotypes was fairly high, with an average of 1.3 ± 0.48 genotypes per host of those with ≥two nematodes. All the sequences of the current study were distributed into two different populations. The sequences of ITS-1 for the first population had the highest similarity to ITS-1 sequence of C. rudolphii B, while the sequences of ITS-1 for the second population had the highest similarity to ITS-1 sequence of C. rudolphii A. This study provides an insight about the genetic divergence of C. rudolphii among P. carbo in Iraq. As well, the results likely support the hypothesis that C. rudolphii represents a complex of at least two sibling species.


2012 ◽  
Vol 88 (1) ◽  
pp. 64-68 ◽  
Author(s):  
G.H. Liu ◽  
W. Zhou ◽  
A.J. Nisbet ◽  
M.J. Xu ◽  
D.H. Zhou ◽  
...  

AbstractTrichuris trichiura and Trichuris suis parasitize (at the adult stage) the caeca of humans and pigs, respectively, causing trichuriasis. Despite these parasites being of human and animal health significance, causing considerable socio-economic losses globally, little is known of the molecular characteristics of T. trichiura and T. suis from China. In the present study, the entire first and second internal transcribed spacer (ITS-1 and ITS-2) regions of nuclear ribosomal DNA (rDNA) of T. trichiura and T. suis from China were amplified by polymerase chain reaction (PCR), the representative amplicons were cloned and sequenced, and sequence variation in the ITS rDNA was examined. The ITS rDNA sequences for the T. trichiura and T. suis samples were 1222–1267 bp and 1339–1353 bp in length, respectively. Sequence analysis revealed that the ITS-1, 5.8S and ITS-2 rDNAs of both whipworms were 600–627 bp and 655–661 bp, 154 bp, and 468–486 bp and 530–538 bp in size, respectively. Sequence variation in ITS rDNA within and among T. trichiura and T. suis was examined. Excluding nucleotide variations in the simple sequence repeats, the intra-species sequence variation in the ITS-1 was 0.2–1.7% within T. trichiura, and 0–1.5% within T. suis. For ITS-2 rDNA, the intra-species sequence variation was 0–1.3% within T. trichiura and 0.2–1.7% within T. suis. The inter-species sequence differences between the two whipworms were 60.7–65.3% for ITS-1 and 59.3–61.5% for ITS-2. These results demonstrated that the ITS rDNA sequences provide additional genetic markers for the characterization and differentiation of the two whipworms. These data should be useful for studying the epidemiology and population genetics of T. trichiura and T. suis, as well as for the diagnosis of trichuriasis in humans and pigs.


2021 ◽  
Author(s):  
Cornelius Kibet Kipyegen ◽  
Charles I. Muleke ◽  
Elick O. Otachi

Abstract Fasciolosis is a neglected trematode infection of public health and veterinary importance caused by Fasciola gigantica and Fasciola hepatica. Molecular analysis using the internal transcribed spacers’ ITS-1 and ITS-2 of nuclear ribosomal DNA is useful in distinguishing Fasciola species. This study aimed to characterize liver flukes from sheep, goats and cattle using these genetic markers. Fifty nine adult Fasciola specimens were collected from livers of naturally infected sheep, goats and cattle at selected abattoirs in Kisumu, Baringo and Narok Counties. Sequence comparison of ITS-1 and ITS-2 sequences of Fasciola isolates from this study and sequences in Genbank was carried out. A maximum likelihood tree was constructed for phylogenetic analysis. Analysis of ITS-1 and ITS-2 rDNA sequences revealed that F. hepatica and F. gigantica caused infection in both cattle and sheep and in goats only F. gigantica caused infection. The sequenced PCR amplicons showed a close relationship between Fasciola species in this study with Fasciola isolates from other regions in the world. Phylogenetic analysis showed that sequences of F. hepatica are similar to the sequence from Spain, China and Tunisia obtained from GenBank. The sequences of F. gigantica in this study have similarity to the sequence from Iran and Burkina Faso. Data from this study provides information that serves as basis for further studies on the distribution of F. gigantica and F. hepatica in other localities in Kenya, and is also important in designing epidemiological and control programmes for zoonotic fascioliasis.


2010 ◽  
Vol 53 (1) ◽  
pp. 141-152 ◽  
Author(s):  
Vitor Fernandes Oliveira de Miranda ◽  
Vanderlei Geraldo Martins ◽  
Antonio Furlan ◽  
Maurício Bacci Jr.

The nuclear ribosomal DNA internal transcribed spacers (ITS1 and ITS2) from leaves of Drosera (Droseraceae) were amplified using "universal" primers. The analysis of the products demonstrated most samples were a molecular mixture as a result of unsuccessful and non-specific amplifications. Among the obtained sequences, two were from Basidiomycota fungi. Homologous sequences of Basidiomycota were obtained from GenBank database and added to a data set with sequences from Drosera leaves. Parsimony analysis demonstrated that one sequence was amplified from an Ustilaginomycetes fungus, and another from a Heterobasidiomycetes. Possibly these fungi were associated to leaves of Drosera, and not because of samples contamination. In order to provide optimization and a better specificity of PCR (polymerase chain reaction), a very successful method was demonstrated using dimethyl sulfoxide (DMSO) and bovine serum albumin (BSA) in reactions.


1995 ◽  
Vol 73 (10) ◽  
pp. 1531-1539 ◽  
Author(s):  
M. Hellgren ◽  
N. Högberg

Genetic variation in Gremmeniella abietina isolated from Pinus sylvestris, Pinus contorta, and Picea abies in southern and northern Fennoscandia was studied with arbitrary primed polymerase chain reaction. Fennoscandian G. abietina isolates were clearly separated into two ecotypically distinct groups based on their amplified banding patterns. Analysis of variance based on amplified fragments, AMOVA, and principal component analysis confirmed the separation of the isolates into the two groups. One group contained isolates associated with a disease syndrome affecting young trees covered by deep snow during winter in northern Fennoscandia. The second group of isolates was found on trees between 15 and 40 years old, scattered throughout the crowns. It occurs throughout Fennoscandia but is most frequent in the southern parts. No size polymorphism was found in fragments resulting after restriction enzyme digestion of internal transcribed spacer and intergenic spacer regions of nuclear ribosomal DNA. An estimate of gene flow between populations calculated based on amplified band frequencies, FST, indicated that there was restricted genetic exchange between populations of the two groups of isolates. Key words: Gremmeniella abietina, arbitrary primed polymerase chain reaction, genetic variation, ecotypes, ribosomal DNA.


2015 ◽  
Vol 90 (1) ◽  
pp. 81-85 ◽  
Author(s):  
J.H. Qiu ◽  
Y. Lou ◽  
Y. Zhang ◽  
Q.C. Chang ◽  
Z.X. Liu ◽  
...  

AbstractThis study examined sequence variability in internal transcribed spacers (ITS) of nuclear ribosomal DNA among Syphacia obvelata and Aspiculuris tetraptera isolates from laboratory mice from different geographical locations in China. ITS1, 5.8S and ITS2 rDNA were amplified separately from adult S. obvelata and A. tetraptera individuals by polymerase chain reaction (PCR), and the amplicons were subjected to sequencing from both directions. The lengths of the sequences of ITS1, 5.8S and ITS2 rDNA from both nematodes were 314 bp and 456 bp, 157 bp, and 273 bp and 419 bp, respectively. The intraspecific sequence variations in S. obvelata ITS1 were 0–0.3%. For A. tetraptera they were 0–0.7% in ITS1 and 0–1.0% in ITS2. However, the interspecific sequence differences among members of the infraorder Oxyuridomorpha were significantly higher, being 54.0–65.5% for ITS1 and 55.3–64.1% for ITS2. Phylogenetic analysis based on the combined partial sequences of ITS1 and ITS2 using three inference methods – Bayesian inference, maximum likelihood and maximum parsimony – revealed that all the S. obvelata and A. tetraptera samples formed independent monophyletic groups. Syphacia obvelata was closer to Syphacia muris than to A. tetraptera, consistent with morphological classification. These results demonstrate that ITS1 and ITS2 rDNA sequences are useful markers for population genetic studies of oxyurid nematodes.


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