Gene mutations and equine health
Certain horses may, unfortunately, carry certain gene mutations which will predispose them to certain diseases such as Glycogen Branching Enzyme Deficiency (GBED) or Recessive or Hereditary Equine Regional Dermal Asthenia (HERDA). This increased genetic susceptibility to disease could mean the horse’s health may be compromised at some stage. Generally, many horses might just be carriers of the disease and have a recessive form of the gene – this means they could pass it on to their offspring although they themselves might never develop the disease. But when two horses mate and both carry recessive genes for the diseases, their offspring will very likely develop the condition. Knowing which disease genes your horses carry mean making a choice of which horses to breed, picking only the healthiest horses and optimising the gene pool. When you come to sell your horses, you can guarantee your buyer of genetically healthy foals or horses.
It is not unusual to be unsure as to which horse is the biological father of a foal. Equine parentage testing is essential to any type of breeding programme. A real guarantee of pedigree can only be scientifically accurate if it the pedigree can be genetically proven. In the past, pedigree was manually recorded, based on close observation. However, these traditional methods of recording ancestry and pedigree leave room for many errors. Parentage DNA testing is 99.9% accurate in cases where the dam, foal and sire are analysed.
Coat colour 7 colour genes
When selecting a horse, the coat colour is a determining factor in the selection process and certain equine coat colours will command higher prices than others. Some coat colours, in certain breeds, are considered to be undesirable.
The basic coat colour genes in horses are White (W), Gray (G), and E and A. Inheriting just one copy of W or G will result in a white or gray horse or mix of both. If the offspring inherit neither W nor G gene variations, then they will exhibit one of a range of possible colours including brown, chestnut, black, and others. Once you test two potential horses for mating and determine what genes they carry, you can predict the possible colour outcomes using a coat colour inheritance chart for horses.
DNA sample collection from horses is by means of hair samples collected from the mane. Hair samples need to be plucked from the horse in order to ensure the hairs have the follicles. The horse will not be injured or feel any pain. The DNA required for a test is found in the hair follicle not the hair shaft. It is thus, important that the hairs have the root and moreover, that a number of hairs are provided (recommended number is between 25- 50 hairs). Each horse’s hair sample must be kept separate.