Horses
Leopard Complex and Eye Health Issues
The leopard complex is a group of white spotting patterns, including the leopard, few-spot leopard, snowcap blanket, lace blanket, spotted blanket, varnish roan, snowflake, and frosted, speckled, and mottled patterns.
The Speed Gene
Horses are an exceptionally athletic species, and even though many of their traditional purposes have faded away over time, some reasons why we, humans, keep them remain. In the past, horses were generally kept for reasons different from today’s. While the number of horses kept solely for sport and status used to be low, today, sport horses, along with leisure horses, represent the majority of the population.
When the Test Results are Negative but the Symptoms are Present
It may have happened to you, your friend, a family member, your dog or your horse. A genetic test was run in the hope of finding a reason behind your or their health problems, but the test results were negative. No questions were answered, and the patient was left undiagnosed. For now.
Genetics in the Face of Doping
At the beginning of the year, the British Horseracing Authority (BHA) announced that racehorses in Britain would undergo testing for gene doping with immediate effect. Gene doping has been banned since 2004 by the World Anti-Doping Agency (WADA) both in humans and animals, and so far, there is no evidence that gene doping is actually taking place in horses.
Basics of Equine Colour Genetics
One of the first things everyone notices about a horse is its colour. Sometimes it’s pretty clear what colour a horse is, while at other times it sparks a full-on discussion — often about foals and young horses — regarding their actual colour. However, genetics can give you a straightforward answer. To some extent — while the main genetic mechanisms are known, some colour variants and their interactions still require clarification.
Popular Sire Effect
You may have noticed that all horses in the 2025 Kentucky Derby are descendants of Secretariat. From a genetic perspective, this is an example of a relatively common trend in breeding: breeding mares to top-performing stallions. These sires are often exceptional in some way and therefore preferred by breeders, who hope their qualities will be passed on to their offspring. However, these breeding decisions inevitably shape the entire breed population, not always for the better. Let’s discuss what is known as the popular sire effect.
Genetic Aspects of Cancer in Horses
The three most common cancers in horses are sarcoids, squamous cell carcinomas and melanomas. All of these are suspected - or even confirmed - to be hereditary cancer syndromes.