Equine Height Variants (LCORL)

Height (H1)


Gene or region:  LCORL / NCAPG

Reference allele: T

Mutant allele: C

Affected Breeds: Many

Research Confidence:                               Moderate confidence, findings reproduced in multiple studies


What it does:  


The domestic horse displays a wide range of size variation, from the tiny Miniature Horses to the towering draft breeds. While height is a complex trait involving a variety of genetic and environmental factors, the breeding systems of domestic animals has led to a small number of genes being responsible for large amounts of variation in several species. One study in the horse has shown four loci can explain up to 83.5% of body size variation. This SNP in particular explained 68.5% of the measured variation in height, with the T allele being associated with small body size, and the C allele with large size (T/C animals displaying an intermediate size). 

n/n - Typical/Average risk; no contribution to height from this variant


LCORL/n - Likely taller/larger than like-bred siblings or breeds


LCORL/LCORL - Likely taller/larger than like bred siblings or breeds (average of 2.9 inches taller than "CC" horses)

LCORL is a transcription factor that has been associated with body size in a variety of species. One study in the horse has suggested that the C allele removes a binding site for TFIID (which is involved with skeletal development), which is further associated with decreased expression of LCORL. This alteration of gene expression could be the molecular basis for the association with body size.




Signer-Hasler H et al., “A genome-wide association study reveals loci influencing height and other conformation traits in horses.” (2012) PLoS One. 7: e37282.  PMID: 22615965


Makvandi-Nejad S et al., “Four loci explain 83% of size variation in the horse.” (2012) PLoS One. 7: e39929.  PMID: 22808074


Metzger J et al., “Expression levels of LCORL are associated with body size in horses.” (2013) PLoS One. 8: e56497.  PMID: 23418579


Tetens J et al., “A genome-wide association study indicates LCORL/NCAPG as a candidate locus for withers height in German Warmblood horses.” (2013) Anim Genet. 44: 467-71.  PMID: 23418885


Boyko AR et al., “Genomic analysis establishes correlation between growth and laryngeal neuropathy in Thoroughbreds.” (2014) BMC Genomics. 15: 259. PMID: 24707981

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