Genes & Genomics

, Volume 35, Issue 4, pp 483–489 | Cite as

Identification and characterization of transposable elements inserted into the coding sequences of horse genes

  • Kung Ahn
  • Jin-Han Bae
  • Jeong-An Gim
  • Ja-Rang Lee
  • Yi-Deun Jung
  • Kyung-Do Park
  • Kyudong Han
  • Byung-Wook Cho
  • Heui-Soo Kim
Research Article


Transposable elements (TEs) are repetitive sequences dispersed throughout mammalian genomes, and they occupy important genetic positions. TEs have been shown to have both harmful and beneficial effects such as exonization, polyadenylation, and/or altering transcription rates in various vertebrate genomes. However, to the best of our knowledge, no study has yet considered the relationship between TEs and horse genes. In this study, we examined the contribution of TEs to the horse genome by collecting TEs inserted within mRNA genes. By screening the abundance, distribution, and orientation of TEs, we found that the majority of TE insertions belong to retroelements and DNA elements, most of which exist in the coding sequences of horse genes. In addition, the MIR, L1, L2, ERVL, and ERVL-MaLR subfamilies were found to be the most abundant in both non-LTR and LTR elements. Retroelements (LTRs, LINEs, and SINEs) among the TEs inserted in the coding sequences showed a preference for antisense orientation. The most pronounced imbalance in insertional orientation was observed in LINEs, which represent 40 % of all TEs in antisense orientation. Through these analyses, we identified that a total of 1310 TEs have been integrated into horse mRNA genes and small fractions of them have been exonized into coding sequences.


Horse Transposable elements (TEs) Retroelements DNA elements 



This work was supported by a grant from the Next generation BioGreen 21 Program (No. PJ0081062011), Rural Development Administration, Republic of Korea.

Supplementary material

13258_2013_57_MOESM1_ESM.ppt (138 kb)
Supplementary Fig. 1. Confidence Interval for Insertional Orientation of Transposable Elements in the Horse Genome. In this study, a total of 625 sense oriented and 685 antisense oriented TEs were detected in the horse genome. This figure illustrates the expected range in distribution for these 1310 TE insertions assuming equal probability (p = 0.5) of TE insertions occurring in either orientation. As can be seen from the binomial distribution, the number of sense and antisense orientations are consistent with a random TE orientational insertion preference. Supplementary material 1 (PPT 137 kb)


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Copyright information

© The Genetics Society of Korea 2013

Authors and Affiliations

  • Kung Ahn
    • 1
  • Jin-Han Bae
    • 1
  • Jeong-An Gim
    • 1
  • Ja-Rang Lee
    • 1
  • Yi-Deun Jung
    • 1
  • Kyung-Do Park
    • 2
  • Kyudong Han
    • 3
  • Byung-Wook Cho
    • 4
  • Heui-Soo Kim
    • 1
  1. 1.Department of Biological SciencesCollege of Natural Sciences, Pusan National UniversityPusanRepublic of Korea
  2. 2.Department of Animal Life and Environment SciencesHankyong National UniversityAnseongRepublic of Korea
  3. 3.Department of Nanobiomedical Science & WCU Research CenterDankook UniversityCheonanRepublic of Korea
  4. 4.Department of Animal Science, College of Life SciencesPusan National UniversityMiryangRepublic of Korea

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