Characterization of internal transcribed spacer-1 and apical membrane antigen-1 sequences provides insights into the genetic diversity of Eimeria tenella strains
https://doi.org/10.47665/tb.39.3.020
- Author:
Loo, S.-S.
1
,
2
;
Mohd-Taib, F.S.
1
;
Khoo, C.-K.
3
;
Wan, K.-L.
1
Author Information
1. Department of Biological Sciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor DE, Malaysia&
2. Agro-Biotechnology Institute, National Institutes of Biotechnology Malaysia, Jalan Bioteknologi, 43400 Serdang, Selangor DE, Malaysia
3. Veterinary Research Institute, Department of Veterinary Services Malaysia, No. 59, Jalan Sultan Azlan Shah, 31400 Ipoh, Perak DR, Malaysia
- Publication Type:Journal Article
- Keywords:
Broiler chicken;
coccidiosis;
inter-strain variation;
ITS-1;
AMA-1
- From:Tropical Biomedicine
2022;39(No.3):476-482
- CountryMalaysia
- Language:English
-
Abstract:
Coccidiosis is a major recurring problem in the poultry industry and is caused by infection of one or more
of the seven Eimeria species known to infect chickens, with Eimeria tenella among the best studied
and economically important. Studies on the genetic diversity of E. tenella strains is essential for the
development of universally acceptable diagnostic markers and vaccines against the disease. Eimeria
tenella internal transcribed spacer-1 (ITS-1) and apical membrane antigen-1 (AMA-1) sequences from
different parts of the world are available in the public domain and therefore provide suitable comparative
markers for genetic diversity study. In this study, the ITS-1 and AMA-1 sequence diversity of two local
E. tenella strains, namely EtNSN6 and EtSGR6 were characterized. Both ITS-1 and AMA-1 sequences
for EtNSN6 and EtSGR6 were retrieved by mapping to their respective genome sequences generated
using next generation sequencing. Multiple sequence alignment of the ITS-1 and AMA-1 sequences
with selected homologous sequences revealed the presence of a total of five and 13 single nucleotide
polymorphisms (SNPs) respectively. All SNPs appeared to occur at random and did not show any unique
pattern based on geographical regions while no insertions and deletions (indels) was found to occur in
the aligned sequences. However, unique bases that defined certain strains were detected. Phylogenetics
analyses performed with Maximum Parsimony (MP) and Maximum Likelihood (ML) methods revealed
similar topology for the internal groups with all the E. tenella ITS-1 and AMA-1 sequences grouped in
the same clade supported by high bootstrap confidence. This confirmed that both EtNSN6 and EtSGR6
samples are E. tenella strains. Sequence comparison and phylogenetics analyses further suggest the
possibility of low genetic diversity among E. tenella strains.
