FREE SHIPPING over $40
OVER 10000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Behavior genetics2024; doi: 10.1007/s10519-024-10186-x

Non-Synonymous Substitutions in Cadherin 13, Solute Carrier Family 6 Member 4, and Monoamine Oxidase A Genes are Associated with Personality Traits in Thoroughbred Horses.

Abstract: Retraining retired racehorses for various purposes can help correct behavioral issues. However, ensuring efficiency and preventing accidents present global challenges. Based on the hypothesis that a simple personality assessment could help address these challenges, the present study aimed to identify genetic markers associated with personality. Eight genes were selected from 18 personality-related candidate genes that are orthologs of human personality genes, and their association with personality was verified based on actual behavior. A total of 169 Thoroughbred horses were assessed for their tractability (questionnaire concerning tractability in 14 types of situations and 3 types of impressions) during the training process. Personality factors were extracted from the data using principal component analysis and analyzed for their association with single nucleotide variants as non-synonymous substitutions in the target genes. Three genes, CDH13, SLC6A4, and MAOA, demonstrated significant associations based on simple linear regression, marking the identification of these genes for the first time as contributors to temperament in Thoroughbred horses. All these genes, as well as the previously identified HTR1A, are involved in the serotonin neurotransmitter system, suggesting that the tractability of horses may be correlated with their social personality. Assessing the genotypes of these genes before retraining is expected to prevent problems in the development of a racehorse's second career and shorten the training period through individual customization of training methods, thereby improving racehorse welfare.
© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Get Full Text
Publication Date: 2024-06-10 PubMed ID: 38856811PubMed Central: 5623013DOI: 10.1007/s10519-024-10186-xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research paper analyzes the genetic markers associated with personality traits in Thoroughbred horses, in an attempt to tailor racehorse retraining by understanding their behavior better. People may be able to better manage and train retired racehorses, improving the animals’ welfare, if they further understand the role of the genetic markers identified in this study, namely CDH13, SLC6A4, and MAOA genes.

Objectives and Hypothesis of the Research

  • The purpose of this study was to identify the genetic markers that may influence a horse’s personality and behavior. The researchers aimed to simplify the retraining process of retired Thoroughbred horses by pinpointing these genetic influences on behavior.
  • The hypothesis presented was that a basic personality assessment could aid in mitigating the global challenges posed by the retraining process of retired racehorses.

Selection and Verification of Genes

  • Eight genes were selected from an original pool of 18 personality-associated candidate genes. These candidate genes were chosen because they had similar counterparts in human genes that influenced personality.
  • The genes’ association with personality traits was verified through assessments of the horses’ real-time behavior.

Personality Analysis of Thoroughbred Horses

  • The researchers studied 169 thoroughbred horses assessing their tractability through a questionnaire which recorded their reactions in 14 different situations and to 3 types of impressions.
  • Additional investigation of the personality factors was achieved by using principal component analysis. The researchers then analyzed the relationship between these factors and single nucleotide variants or non-synonymous substitutions in the target genes.

Identification of Genetic Markers and their Associations

  • Three genes – Cadherin 13 (CDH13), Solute Carrier Family 6 Member 4 (SLC6A4), and Monoamine Oxidase A (MAOA) – demonstrated significant associations with the horses’ personality traits according to a simple linear regression analysis. This marks the first time these genes have been associated with temperament in Thoroughbred horses.
  • All identified genes, including another previously discovered gene known as HTR1A, are involved in the serotonin neurotransmitter system. This finding suggests a correlation between the horses’ social personalities and their tractability or responsiveness to handling and training.

Projecting the Practical Applications

  • The finding expects that, with these genotypes’ assessments before retraining, the second career development problems in racehorses may be prevented. This process can also help in shortening the training period by customizing training techniques per individual horse based on their identified personality factors.
  • This approach will aid in better horse management, accelerate retraining timelines and ultimately improve the welfare of the horses.

Cite This Article

APA
Yokomori T, Tozaki T, Ohnuma A, Ishimaru M, Sato F, Hori Y, Segawa T, Itou T. (2024). Non-Synonymous Substitutions in Cadherin 13, Solute Carrier Family 6 Member 4, and Monoamine Oxidase A Genes are Associated with Personality Traits in Thoroughbred Horses. Behav Genet. https://doi.org/10.1007/s10519-024-10186-x

Publication

Behavior genetics
ISSN: 1573-3297
NlmUniqueID: 0251711
Country: United States
Language: English

Researcher Affiliations

Yokomori, Tamu
  • Department of Preventive Veterinary Medicine and Animal Health, Nihon University Veterinary Research Center, Fujisawa, Kanagawa, Japan.
Tozaki, Teruaki
  • Genetic Analysis Department, Laboratory of Racing Chemistry, Utsunomiya, Tochigi, Japan. ttozaki@lrc.or.jp.
Ohnuma, Aoi
  • Genetic Analysis Department, Laboratory of Racing Chemistry, Utsunomiya, Tochigi, Japan.
Ishimaru, Mutsuki
  • Japan Racing Association, Hidaka Training and Research Center, Urakawa, Hokkaido, Japan.
Sato, Fumio
  • Japan Racing Association, Hidaka Training and Research Center, Urakawa, Hokkaido, Japan.
Hori, Yusuke
  • Graduate School of Arts and Sciences, Department of Life Sciences, The University of Tokyo, Meguro, Tokyo, Japan.
Segawa, Takao
  • Department of Preventive Veterinary Medicine and Animal Health, Nihon University Veterinary Research Center, Fujisawa, Kanagawa, Japan.
Itou, Takuya
  • Department of Preventive Veterinary Medicine and Animal Health, Nihon University Veterinary Research Center, Fujisawa, Kanagawa, Japan. itou.takuya@nihon-u.ac.jp.

References

This article includes 50 references
  1. Akimova E, Lanzenberger R, Kasper S. The serotonin-1A receptor in anxiety disorders.. Biol Psychiatry 66:627–635.
    doi: 10.1016/j.biopsych.2009.03.012pubmed: 19423077google scholar: lookup
  2. Andresen T, Lunden D, Drewes AM. Pain sensitivity and experimentally induced sensitisation in red haired females.. Scand J Pain 2:3–6.
    doi: 10.1016/j.sjpain.2010.08.005pubmed: 29914002google scholar: lookup
  3. Canli T, Zhao Z, Desmond JE. An fMRI study of personality influences on brain reactivity to emotional stimuli.. Behav Neurosci 115:33–42.
    doi: 10.1037/0735-7044.115.1.33pubmed: 11256451google scholar: lookup
  4. Carroll JC, Boyce-Rustay JM, Millstein R. Effects of mild early life stress on abnormal emotion-related behaviors in 5-HTT knockout mice.. Behav Genet 37:214–222.
    doi: 10.1007/s10519-006-9129-9pubmed: 17177116google scholar: lookup
  5. Cattell RB. The scree test for the number of factors.. Multivar Behav Res 1:245–276.
    doi: 10.1207/s15327906mbr0102_10google scholar: lookup
  6. Choi Y, Yoon M. The effects of androstenone on the plasma serotonin, β-endorphin, and cortisol concentrations in Thoroughbred horses.. Anim (Basel) 11:1694.
    doi: 10.3390/ani11061694google scholar: lookup
  7. Cooper JJ. Comparative learning theory and its application in the training of horses.. Equine Vet J 27:39–43.
    doi: 10.1111/j.2042-3306.1998.tb05144.xgoogle scholar: lookup
  8. Duberstein KJ, Gilkeson JA. Determination of sex differences in personality and trainability of yearling horses utilizing a handler questionnaire.. Appl Anim Behav Sci 128:57–63.
    doi: 10.1016/j.applanim.2010.09.012google scholar: lookup
  9. Farries G, McGettigan PA, Gough KF. Genetic contributions to precocity traits in racing thoroughbreds.. Anim Genet 49:193–204.
    doi: 10.1111/age.12622pubmed: 29230835google scholar: lookup
  10. Forero A, Rivero O, Wäldchen S. Cadherin-13 deficiency increases dorsal raphe 5-HT neuron density and prefrontal cortex innervation in the mouse brain.. Front Cell Neurosci 11:307.
    doi: 10.3389/fncel.2017.00307pubmed: 29018333pmc: 5623013google scholar: lookup
  11. Gazendam FJ, Kamphuis JH, Eigenhuis A. Personality predicts individual variation in fear learning: a multilevel growth modeling approach.. Clin Psychol Sci 3:175–188.
    doi: 10.1177/2167702614535914google scholar: lookup
  12. Giakoumaki SG, Roussos P, Tsapakis EM. Cognitive and personality analysis of startle reactivity in a large cohort of healthy males.. Biol Psychol 94:582–591.
    doi: 10.1016/j.biopsycho.2013.09.005pubmed: 24051230google scholar: lookup
  13. Gottschalk MG, Domschke K. Novel developments in genetic and epigenetic mechanisms of anxiety.. Curr Opin Psychiatry 29:32–38.
    doi: 10.1097/YCO.0000000000000219pubmed: 26575296google scholar: lookup
  14. Guo A, Hirai R, Ohashi A. Personality prediction from task-oriented and open-domain human-machine dialogues.. Sci Rep 14:3868.
    doi: 10.1038/s41598-024-53989-ypubmed: 38366048pmc: 10873327google scholar: lookup
  15. Hall Angerås M. Skador inom ridsporten - förebyggande av största vikt [Horse-related injuries - prevention very important].. Lakartidningen 116:FPT6.
  16. Hartmann E, Rehn T, Christensen JW. From the horse’s perspective: investigating attachment behaviour and the effect of training method on fear reactions and ease of handling-A pilot study.. Anim (Basel) 11:457.
    doi: 10.3390/ani11020457google scholar: lookup
  17. Hausberger M, Bruderer C, Le Scolan N. Interplay between environmental and genetic factors in temperament/personality traits in horses (Equus caballus).. J Comp Psychol 118:434–446.
    doi: 10.1037/0735-7036.118.4.434pubmed: 15584780google scholar: lookup
  18. Hoffmann MF, Bernstorff M, Kreitz N. Horse-related injury patterns: a single center report.. J Orthop Surg Res 18:83.
    doi: 10.1186/s13018-023-03549-3pubmed: 36732813pmc: 9893574google scholar: lookup
  19. Holcomb KE, Stull CL, Kass PH. Unwanted horses: the role of nonprofit equine rescue and sanctuary organizations.. J Anim Sci 88:4142–4150.
    doi: 10.2527/jas.2010-3250pubmed: 20709875google scholar: lookup
  20. Holcomb KE, Stull CL, Kass PH. Characteristics of relinquishing and adoptive owners of horses associated with U.S. nonprofit equine rescue organizations.. J Appl Anim Welf Sci 15:21–31.
    doi: 10.1080/10888705.2012.624049pubmed: 22233213google scholar: lookup
  21. Holtby AR, McGivney BA, Browne JA. Variation in salivary cortisol responses in yearling Thoroughbred racehorses during their first year of training.. PLoS ONE 18:e0284102.
    doi: 10.1371/journal.pone.0284102pubmed: 37023093pmc: 10079128google scholar: lookup
  22. Hori Y, Tozaki T, Nambo Y. Evidence for the effect of serotonin receptor 1A gene (HTR1A) polymorphism on tractability in Thoroughbred horses.. Anim Genet 47:62–67.
    doi: 10.1111/age.12384pubmed: 26763159google scholar: lookup
  23. Ijichi C, Collins LM, Creighton E. Harnessing the power of personality assessment: subjective assessment predicts behaviour in horses.. Behav Processes 96:47–52.
    doi: 10.1016/j.beproc.2013.02.017google scholar: lookup
  24. Ijichi C, Collins LM, Elwood RW. Pain expression is linked to personality in horses.. Appl Anim Behav Sci 152:38–43.
    doi: 10.1016/j.applanim.2013.12.007google scholar: lookup
  25. Jacobs LN, Staiger EA, Albright JD. The MC1R and ASIP coat color loci may impact behavior in the horse.. J Hered 107:214–219.
    doi: 10.1093/jhered/esw007pubmed: 26884605pmc: 4885240google scholar: lookup
  26. Joos E, Vansteenwegen D, Hermans D. Worry as a predictor of fear acquisition in a nonclinical sample.. Behav Modif 36:723–750.
    doi: 10.1177/0145445512446477pubmed: 22679241google scholar: lookup
  27. Kalbfleisch TS, Rice ES, DePriest MS. Improved reference genome for the domestic horse increases assembly contiguity and composition.. Commun Biol 1:197.
    doi: 10.1038/s42003-018-0199-zpubmed: 30456315pmc: 6240028google scholar: lookup
  28. Kanen JW, Arntz FE, Yellowlees R. Serotonin depletion amplifies distinct human social emotions as a function of individual differences in personality.. Transl Psychiatry 11:81.
    doi: 10.1038/s41398-020-00880-9pubmed: 33518708pmc: 7847998google scholar: lookup
  29. Kim J, Park Y, Kim EJ. Relationship between oxytocin and serotonin and the fearfulness, dominance, and trainability of horses.. J Anim Sci Technol 63:453–460.
    doi: 10.5187/jast.2021.e29pubmed: 33987618pmc: 8071747google scholar: lookup
  30. Kolenikov S, Angeles G. Socioeconomic status measurement with discrete proxy variables: is principal component analysis a reliable answer?. Rev Income Wealth 55:128–165.
    doi: 10.1111/j.1475-4991google scholar: lookup
  31. Kolla NJ, Bortolato M. The role of monoamine oxidase A in the neurobiology of aggressive, antisocial, and violent behavior: a tale of mice and men.. Prog Neurobiol 194:101875.
    doi: 10.1016/j.pneurobio.2020.101875pubmed: 32574581pmc: 7609507google scholar: lookup
  32. Le Scolan N, Hausberger M, Wolff A. Stability over situations in temperamental traits of horses as revealed by experimental and scoring approaches.. Behav Processes 41:257–266.
    doi: 10.1016/s0376-6357(97)00052-1pubmed: 24896858google scholar: lookup
  33. Librado P, Khan N, Fages A. The origins and spread of domestic horses from the western eurasian steppes.. Nature 598:634–640.
    doi: 10.1038/s41586-021-04018-9pubmed: 34671162pmc: 8550961google scholar: lookup
  34. Maney DL. Polymorphisms in sex steroid receptors: from gene sequence to behavior.. Front Neuroendocrinol 47:47–65.
    doi: 10.1016/j.yfrne.2017.07.003pubmed: 28705582google scholar: lookup
  35. Momozawa Y, Takeuchi Y, Tozaki T. SNP detection and radiation hybrid mapping in horses of nine candidate genes for temperament.. Anim Genet 38:81–83.
    doi: 10.1111/j.1365-2052.2006.01541.xpubmed: 17257195google scholar: lookup
  36. Näslund J, Studer E, Nilsson K. Serotonin depletion counteracts sex differences in anxiety-related behaviour in rat.. Psychopharmacology 230:29–35.
    doi: 10.1007/s00213-013-3133-6pubmed: 23681161google scholar: lookup
  37. Oliveira VEM, Bakker J. Neuroendocrine regulation of female aggression.. Front Endocrinol (Lausanne) 13:957114.
    doi: 10.3389/fendo.2022.957114pubmed: 36034455google scholar: lookup
  38. Pettersson R, Hagsäter SM, Eriksson E. Serotonin depletion eliminates sex differences with respect to context-conditioned immobility in rat.. Psychopharmacology 233:1513–1521.
    doi: 10.1007/s00213-016-4246-5pubmed: 26905688google scholar: lookup
  39. Redies C, Hertel N, Hübner CA. Cadherins and neuropsychiatric disorders.. Brain Res 1470:130–144.
    doi: 10.1016/j.brainres.2012.06.020pubmed: 22765916google scholar: lookup
  40. Staes N, Sherwood CC, Freeman H. Serotonin receptor 1A variation is associated with anxiety and agonistic behavior in chimpanzees.. Mol Biol Evol 36:1418–1429.
    doi: 10.1093/molbev/msz061pubmed: 31045220pmc: 7968385google scholar: lookup
  41. Stamps J, Groothuis TG. The development of animal personality: relevance, concepts and perspectives.. Biol Rev Camb Philos Soc 85:301–325.
    doi: 10.1111/j.1469-185X.2009.00103.xpubmed: 19961473google scholar: lookup
  42. Stowe CJ, Kibler ML. Characteristics of adopted Thoroughbred racehorses in second careers.. J Appl Anim Welf Sci 19:8–89.
    doi: 10.1080/10888705.2015.1094392google scholar: lookup
  43. Tozaki T, Ohnuma A, Kikuchi M. Rare and common variant discovery by whole-genome sequencing of 101 Thoroughbred racehorses.. Sci Rep 11:16057.
    doi: 10.1038/s41598-021-95669-1pubmed: 34362995pmc: 8346562google scholar: lookup
  44. Visser EK, Van Reenen CG, Blokhuis MZ. Does horse temperament influence horse-rider cooperation?. J Appl Anim Welf Sci 11:267–284.
    doi: 10.1080/10888700802101254pubmed: 18569223google scholar: lookup
  45. Visser EK, VanDierendonck M, Ellis AD. A comparison of sympathetic and conventional training methods on responses to initial horse training.. Vet J 181(1):48–52.
    doi: 10.1016/j.tvjl.2009.03.009pubmed: 19375363google scholar: lookup
  46. Vitaro F, Brendgen M, Barker ED. Subtypes of aggressive behaviors: a developmental perspective.. Int J Behav Dev 30:12–19.
    doi: 10.1177/0165025406059968google scholar: lookup
  47. Westberg L, Eriksson E. Sex steroid-related candidate genes in psychiatric disorders.. J Psychiatry Neurosci 33:319–330.
    pubmed: 18592033pmc: 2440794
  48. Yokomori T, Ohnuma A, Tozaki T. Identification of personality-related candidate genes in Thoroughbred racehorses using a bioinformatics-based approach involving functionally annotated human genes.. Anim (Basel) 13:769.
    doi: 10.3390/ani13040769google scholar: lookup
  49. Zanettini C, Carola V, Lo Iacono L. Postnatal handling reverses social anxiety in serotonin receptor 1A knockout mice.. Genes Brain Behav 9:26–32.
    doi: 10.1111/j.1601-183X.2009.00531.xpubmed: 19740091google scholar: lookup
  50. Ziegler GC, Ehlis AC, Weber H. A common CDH13 variant is associated with low agreeableness and neural responses to working memory tasks in ADHD.. Genes (Basel) 12:1356.
    doi: 10.3390/genes12091356pubmed: 34573337google scholar: lookup

Citations

This article has been cited 2 times.
  1. Yokomori T, Tozaki T, Segawa T, Itou T. Genomic regions and candidate genes associated with forehead whorl positioning in Thoroughbred horses. J Equine Sci 2025;36(1):11-18.
    doi: 10.1294/jes.36.11pubmed: 40115733google scholar: lookup
  2. Azcona F, Molina A, Demyda-Peyrás S. Genomic-Inbreeding Landscape and Selection Signatures in the Polo Argentino Horse Breed. Int J Mol Sci 2024 Dec 24;26(1).
    doi: 10.3390/ijms26010026pubmed: 39795883google scholar: lookup
Subscribe to our newsletter
Join 99,727 horse owners like you who receive our email updates on horse health and nutrition.