A chromosome inversion near the KIT gene and the Tobiano spotting pattern in horses

Cytogenet Genome Res. 2007;119(3-4):225-30. doi: 10.1159/000112065. Epub 2008 Feb 1.


Tobiano is a white spotting pattern in horses caused by a dominant gene, Tobiano(TO). Here, we report TO associated with a large paracentric chromosome inversion on horse chromosome 3. DNA sequences flanking the inversion were identified and a PCR test was developed to detect the inversion. The inversion was only found in horses with the tobiano pattern, including horses with diverse genetic backgrounds, which indicated a common genetic origin thousands of years ago. The inversion does not interrupt any annotated genes, but begins approximately 100 kb downstream of the KIT gene. This inversion may disrupt regulatory sequences for the KIT gene and cause the white spotting pattern.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Albumins / genetics
  • Animals
  • Breeding
  • Chromosome Inversion / genetics*
  • Chromosomes, Mammalian / genetics
  • Genetic Markers
  • Haplotypes
  • Horses / genetics*
  • In Situ Hybridization, Fluorescence
  • Molecular Sequence Data
  • Pigmentation / genetics*
  • Polymerase Chain Reaction
  • Polymorphism, Single Nucleotide / genetics
  • Proto-Oncogene Proteins c-kit / genetics*
  • Vitamin D-Binding Protein / genetics


  • Albumins
  • Genetic Markers
  • Vitamin D-Binding Protein
  • Proto-Oncogene Proteins c-kit

Associated data

  • GENBANK/EF442014