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Licensed Unlicensed Requires Authentication Published by De Gruyter December 28, 2016

Intra and inter species genetic variability of transferrin receptor gene regions in Trypanosoma evansi isolates of different livestock and geographical regions of India

Souti Prasad Sarkhel, S.K. Gupta, Jyoti Kaushik, Jarnail Singh, Vijesh Kumar Saini, Sanjay Kumar and Rajender Kumar
From the journal Acta Parasitologica


Trypanosoma evansi, the aetiological agent of Surra affects a wide range of livestock and wild animals in India. In the present study, we studied intra- and inter species genetic variability in the transferrin receptor encoding gene regions (ESAG6/7 gene region) of T. evansi isolates by cloning, sequencing and phylogenetic study collected from camel, cattle, donkeys and ponies from North-Western and Central India. The nucleotide sequence variation of ESAG6/7 gene region between Indian T. evansi isolates was up to 17.7% and amino acid sequence variation was up to 31%. Twenty nine clones from six T. evansi isolates from geographical regions of India were included into Clade 1, 5, 6, 7 and 9 consisting of ESAG6 variants reported among T. evansi isolates from South-east Asia and South America. The cladogram indicated a relation between the host species and the genetic variability in the hyper-variable region of ESAG6 gene. Analysis of the Indian ESAG6 variants and their respective Clade positions presented a host specific distribution indicating homogenous parasite population in their respective animal hosts.

  1. Conflict of Interest Statement: All authors disclose that they have no financial and personal relationships with other people or organization that could inappropriately influence their work, including employment, consultancies, stock ownership, honoraria, paid expert testimony, patent applications/registration, and grants or other funding.


    All authors certify that the animal experimentations carried out in the present work after approval of Institute Animal Ethic Committee and as per guidelines set by the Committee for the Purpose of Control and Supervision of Experiments on Animals (CPCSEA), Animal Welfare Division, Government of India.


The work was performed at ICAR-National Research Centre on Equines, Hisar, India. The financial support for this study provided by Indian Council of Agricultural Research, New Delhi under National Fellow project is gratefully acknowledged.


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Received: 2016-6-10
Revised: 2016-9-22
Accepted: 2016-10-14
Published Online: 2016-12-28
Published in Print: 2017-3-1

© 2017 W. Stefański Institute of Parasitology, PAS