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Genic Variant Detection of Caspian Horse Using High-throughput Sequencing Technology

Recently, new advanced high-throughput sequencing technology as a novel tool has opened the way to study of genomic variants and functional information stored within farm animals.

The Caspian horse is one of the valuable horses ever exist in the world. Hence, propose of this study was to investigate genetic variants of single nucleotide polymorphisms, insertion and deletions and copy number variations within the genome of Caspian horse and their involved biological pathways. Using high-throughput sequencing technology, we generated 108 Gb (Average depth of 45.8) of DNA sequence from three Caspian horse mares resulting in an average of 14.41X coverage and 76.4% covered with reference genome. Using a stringent filtering method, we identified 1666717 single nucleotide polymorphisms, 358020 insertion and deletions, and 3109 copy number variations. Functional clustering analysis of genic variants revealed that most of the genetic variants in the Caspian horse’s genome were enriched in nervous system, GTP-related signal transduction, cellular morphogenesis, cytoskeleton organization, vascular development and cellular movement. Moreover, we have detected structural variations as like as inversion, intra- and inter-chromosomal translocations, large insertion and deletions which could be useful for marker based population genetic investigation.

Keywords, High-throughput sequencing, Caspian horse, Genic variants, Biological pathways.


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Arefnezhad B.1, Kohram H.1, Moradi Shahre-Babak M.1, Shakeri M.1, Dong Y.5, Zhang X.5, Wang W.5, Hoseini Salekdeh Gh.*4

۱Department of Animal Science, University of Tehran, Karaj, Iran.

۲ State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.

۳Agricultural Biotechnology Research Institute of Iran (ABRII), Karaj, Iran.


*Corresponding Author: Kohram H, Hoseini Salekdeh Gh. Tel: 02632248082 Email:,


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