Horse DNA Test Results Interpreter

Each result shows which two copies (alleles) your horse carries at a specific gene. For example, E/e means the horse has one dominant black-pigment copy (E) and one recessive red-pigment copy (e). This interpreter translates every result into plain English so you know exactly what each code means.

E/E means the horse is homozygous for black pigment and cannot produce chestnut or sorrel foals. E/e means the horse shows a black-based color but carries the red gene — chestnuts are possible depending on the breeding partner. e/e means the horse has a red (chestnut or sorrel) base and cannot produce black-based foals unless bred to a black-pigment horse.

N/Cr means your horse carries one copy of the cream gene. On a chestnut base this produces palomino; on a bay base it produces buckskin; on a black base it produces smoky black, which can look similar to a plain black horse. Each foal has a 50% chance of inheriting the cream copy.

Lethal White Overo (LWO) occurs when a foal inherits two copies of the Frame Overo gene (O/O). These foals are born with a non-functional digestive tract and do not survive. If your horse's DNA report shows O/n (one frame copy), it is critical that you DNA test any breeding partner and confirm they are not also a frame carrier before proceeding with breeding.

Yes. Several genes are invisible in certain horses. A red (ee) horse can carry Agouti (A) or Silver (Z) that only appears in offspring who inherit black pigment from the other parent. Cream on a black horse produces smoky black, which is nearly indistinguishable from plain black without testing. This interpreter flags all known hidden-gene situations for your specific test result.

Most gray horses do lighten significantly over time, often going through a salt-and-pepper or dapple phase. A G/G horse (homozygous gray) will gray and passes the gene to every foal. A G/g horse will also gray but only passes the gene to roughly 50% of foals. Gray horses have a statistically higher rate of melanoma — discuss regular monitoring with your veterinarian.

A horse that tests To/To is homozygous tobiano, meaning it will pass the tobiano gene to 100% of its foals. Every foal it produces will be tobiano patterned regardless of the other parent's genetics. A heterozygous horse (To/n) passes tobiano to approximately 50% of foals.

No. This tool is an educational interpreter — it explains what results you have already received from an accredited lab. It cannot generate, verify, or substitute for official DNA test results. For breeding, registration, and medical decisions always use results from a certified equine genetics laboratory.

The interpreter includes preset formats for UC Davis Veterinary Genetics Laboratory, Etalon Diagnostics, and Animal Genetics. A universal format is also available if your lab uses different notation. All formats cover the same nine core loci: Extension, Agouti, Cream, Dun, Silver, Gray, Roan, Tobiano, and Frame Overo.

The interpreter provides a ready-to-use settings summary at the bottom of your results. Copy those settings directly into the Horse Education Online Coat Color Calculator to run Mendelian breeding predictions and see the percentage chance of each possible foal color from any cross.