Each horse in Horse Reality consists of around 50 genes. Together they determine how the horse looks, moves, how healthy and fertile it is, and where its talents may lie. You can find all the information about the genes of your horse in the various tabs of its profile.
The genes in Horse Reality are separated into five groups, commonly called "stats".
¶ Inheritance of Alleles
In Horse Reality every horse has two copies of most genes, as they do in real life. Genes can often have different variants. These are called alleles. When you breed your horses, the foal will always receive one allele from the dam and one allele from the sire for each trait. Since both parents also have two alleles of each genetic trait, it is up to chance which two out of four possible alleles the foal receives. This means that the foal could have better or worse traits than its parents and that there is, for example, a possibility that you breed two black jumping horses and the foal is neither black nor good at jumping. It also means that if you breed the same parents again, the next foal may actually be a black jumping horse. The more you learn about genetics, the better you will know what to expect when you breed two horses.
Note: Height is the only gene in Horse Reality that is not inherited via two alleles.
¶ Colour Genetics
Just like in real life, the alleles of colour genes on Horse Reality are either recessive, dominant, or incomplete dominant. In short, dominant alleles trump recessive ones. It's customary to write dominant alleles with a capital letter and recessive alleles with a lowercase letter. When a horse has two copies of the same allele, this is called homozygous. When the horse has 2 different alleles of a gene, it's called heterozygous.
¶ The Flaxen Gene as an Example
Remember that a horse has two copies (alleles) of each gene, one inherited from its dam and one from its sire. A foal may receive two different copies from each parent (heterozygous). If the sire is chestnut with a dark mane and the dam is chestnut with a blonde mane, will the foal's mane be dark or blonde? That depends on which of the two traits is dominant over the other.
One gene in Horse Reality that is responsible for a blonde mane is the flaxen gene. Flaxen works only on chestnut-based horses (e/e extension genotype) and it is recessive, meaning that only horses with two copies of the flaxen allele (f/f) have a blonde mane:
- F/F = Red mane
- F/f = Red mane
- f/f = Blonde mane
In the following example (Punnett square), two chestnut-based horses are bred together. The sire has two copies (F/F) of the allele that results in a dark mane. The dam has two copies of the recessive version (f/f), which results in a blonde mane. All possible foals of this combination would end up having one copy of each version (F/f). Because the dark mane is dominant, the foal ends up having a dark mane:-
| Dam | |||
| Sire | f | f | |
| F | F/f | F/f | |
| F | F/f | F/f | |
Things get more interesting if you breed a sire and a dam who each have a copy of each version (F/f), as you can see in the following table. The resulting foal has a 25% chance to get both copies of the dominant allele (F/F) and therefore a dark mane. It has a 50% chance to get one copy of each version (F/f) and therefore a dark mane. And it has a 25% chance to get both copies of the recessive allele (f/f) and therefore a blonde mane:
| Dam | |||
| Sire | F | f | |
| F | F/F | F/f | |
| f | F/f | f/f | |
This is why in colour genetics, we differentiate between the genotype and the phenotype. The term genotype refers to the full genetic information while phenotype refers to everything we can observe from the outside. To continue the example above, a horse's phenotype could be "dark mane", but its genotype could either be F/f or F/F. We don't know that just by looking at the horse, but we can learn it from observing the offspring this horse produces and by looking at the pedigree. A horse with the genotype F/F will never have a foal with a blonde mane (at least not due to the flaxen gene).
¶ Genetic Potential, Conformation and Health
These three stats are also inherited via alleles in Horse Reality, but they are not recessive or dominant. Instead, they have a numeric value that is either known (genetic potential) or hidden behind a verbal label (conformation, health). This numeric value is the average of two alleles - each allele, as well as their average, can lie between 0 and 100. When breeding two horses, the foal inherits by chance one allele of its dam and one allele of its sire, each with a small variation (RNG).
¶ Numeric Value
The numeric value of a horse's stats is the easiest to see for its genetic potential. It says, for example, that your horse has an acceleration of 80:
The conformation stats are hidden behind a verbal label. It will say, for example, that your horse's posture is "good". This means that the horse's walk stat could be any number between 70 and 84. Read more about that in the article about conformation stats. Health stats work similarly.
¶ Averaged Alleles
The number or label you see is the average of two numeric alleles. Let's stay with the example of the "good" walk. This means the average of the two “walk”-alleles that your horse inherited from its parents lies between 70 and 84 points. But you have no way of knowing which points exactly, and which points each of the two alleles has. Here is a table with just some of the possibilities:
| Allele 1 | Allele 2 | Stat |
| 50 (“Below average”) | 95 (“Very good”) | 72.5 (“Good”) |
| 70 (“Good”) | 70 (“Good”) | 70 (“Good”) |
| 84 (“Good”) | 65 (“Average”) | 74.5 (“Good”) |
| 40 (“Below average”) | 100 (“Very good”) | 70 (“Good”) |
Note that with some horses, the two alleles will be the same or very close to each other, while other horses will have alleles that differ a lot. Your horse’s performance in conformation shows or competitions will always depend on the average of the two alleles, which is the trait of your horse. The individual alleles are important for breeding, since your horse will give its foal only one of its two alleles by chance. Looking carefully at your horse’s offspring might give you some insight into its alleles. If your horse has many foals, and all of them have the “Good” trait in the “Walk” category, it is very likely that the two “Walk”-alleles of your horse are close to each other and both fall within the “Good” range. If some of the foals have a “Below average” and some a “Very good” in the “Walk” category, chances are that your horse has two alleles with values that are very far from each other. However, you can never be sure since the foal’s genetic traits are also influenced by its other parent and a variation created by a random number generator.
¶ RNG (Random Number Generator)
All the numeric genes are subject to variation by a few points. This means your foal gets one allele of its sire, and one of its dam, but both may be varied upwards or downwards by a few points. This was added to the game to simulate the effects the external world has on pregnancies in real life.