Dr. Elizabeth Esdaile and a research team from the University of California Davis Veterinary Genetics
Laboratory screened 19 unregistered Shetland ponies from one ranch for a variety of white pattern
markers.

The researchers found inexplicable coat colors in 14 of the ponies, and began looking for other
dominant white variants. They found that all 14 were heterozygous for the W13 gene. Prior to this
discovery, W13 had only been found in two Quarter Horses-Peruvian Paso crosses and one Australian
miniature horse family.

All ponies with the W13 allele had all-white coats with pink skin phenotype, no matter which other
white spotting variants were present.

The scientists also tested hair samples of 25 miniature horses and five Shetland ponies, each of which
their owners called “white.” Two of the miniature horses were heterozygous for the W13 gene. There
were no homozygous ponies; researchers say that homozygosity is most likely lethal.

The scientists noted that the Shetland ponies that had the W13 allele were not registered, and none of
the registered Shetland ponies had the allele. The team suggested that the unregistered Shetlands may
have some Miniature Horse breeding in their past.

The researchers said these results highlight the presence of the W13 allele in both Shetland ponies and
the American Miniature Horse, and the importance of testing for the variant since inheriting two copies
of the gene is most likely lethal.

Read the study here.

Read more at HorseTalk.

The post Two Copies Of White Coat Allele May Be Lethal In Ponies appeared first on Horse Racing News | Paulick Report.

Source of original post

Researchers at the University of California-Davis have discovered two genetic mutations responsible for the unusual eye color that is desired by Paso Fino breeders. The tiger eye trait is autosomal recessive, meaning one copy of the mutated gene must be inherited from each parent.

Most tiger-eyed horses have inherited two copies of the Tiger-eye 1 allele, but some have one copy of each mutation (Tiger-eye 1 and Tiger-eye 2). The researchers tested 196 related breeds and have not found the mutation in any other breed but the Puerto Rican Paso Fino. 

UC-Davis now offers a genetic test for tiger eye. This test allows breeders desiring a tiger-eyed horse to strategically plan pairings.   

Read more at EQUUS. 

The post Eye Of The Tiger: Genetic Reason Behind ‘Tiger Eye’ Discovered appeared first on Horse Racing News | Paulick Report.

Source of original post

The scientists were successful in removing the myostatin gene, which inhibits skeletal muscle mass development. This gene plays a significant role in gene-based distance aptitude of racehorses. Their gene editing techniques achieved 96.2 percent efficacy.

The team noted that additional research to determine an efficient manner of editing embryos was needed before this technique could be used to improve the athletic performance of horses. The team's long-term goal is to identify alleles that give a horse a natural sporting advantage and then incorporate them to allow other horses the same characteristics. They consider this technique a precision breeding strategy as it can deliver results to only one generation.

Read the full study here.

Read more at HorseTalk.

The post The Need For Speed: Genetic Editing Can Create Faster Horses appeared first on Horse Racing News | Paulick Report.

Source of original post