Genetic influence of a STAU2 frameshift mutation and RELN regulatory elements on performance in Icelandic horses

Abstract

Selection for performance in horse breeding benefits from precise genetic insights at a molecular level, but knowledge remains limited. This study used whole-genome sequences of 39 elite and non-elite Icelandic horses to identify candidate causal variants linked to previously identified haplotypes in the STAU2 and RELN genes affecting pace and other gaits. A frameshift variant in linkage disequilibrium with the previously identified haplotypes in the STAU2 gene (r2 = 0.85) was identified within a predicted STAU2 transcript. This variant alters the amino acid sequence and introduces a premature stop codon but does not appear harmful or disease-causing and is potentially unique to equine biology. A large portion of the RELN haplotype overlapped with an H3K27me3 modification mark, suggesting a regulatory role of this region. Despite the small sample size, the RELN haplotype's effects were validated for t & ouml;lt, trot, and canter/gallop. Additionally, the RELN haplotype significantly influenced the age at which horses were presented for breeding field tests, indicating a potential role of the region in precocity and trainability. Functional experiments are needed to further investigate the regions' influences on biological processes and their potential impact on horse performance.

Keywords

Equine; Gait quality; Trainability; Precocity; Whole-genome sequencing; Candidate causal variant

Published in

Scientific Reports
2025, volume: 15, number: 1, article number: 11641
Publisher: NATURE PORTFOLIO

SLU Authors

• Sigurðardóttir, Heiðrún

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    
  • Agricultural University of Iceland (LBHI)

• Eriksson, Susanne

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Niazi, Adnan

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Rhodin, Marie

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Lindgren, Gabriella

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    
  • University of Leuven (KU Leuven)

UKÄ Subject classification

Medical Bioscience
Genetics and Genomics

Publication identifier

• DOI: https://doi.org/10.1038/s41598-025-95593-8

Permanent link to this page (URI)

https://res.slu.se/id/publ/141576