ENCYCLOPEDIA Rancholi
Equine Genetic Analysis for Crossing

Paint Bay X Dun Dark Brown

Wilson Chavioli Filho
Wilson Chavioli Filho Equine genetics enthusiast
Creator of the Rancholi App
Genetic Analysis

Sire Paint Bay on dam Dun Dark Brown

In this article, we will explore the genetic possibilities of coat colors for the crossing between a stallion Paint Bay and a mare Dun Dark Brown. Equine genetics is a universe of combinations where dominant and recessive alleles determine the final coat of each individual.

On one side, we have the stallion Paint Bay. Genetically, it presents the base genotype E/_ A/_ To/n. The (To) gene acts on the base coat forming large, well-defined white patches across the body and legs. Many cases also inherit blue eyes. This coat is based on Bay.

On the other side, the mare Dun Dark Brown contributes with its genetics based on E/_ A/_ D/n. The Dun gene acts on the base color, adding the characteristic dark dorsal stripe. In some cases it lightens the body tone and may also produce zebra-like leg markings. This coat is based on Dark Brown.

Quando combinamos esses códigos genéticos, criamos uma matriz de probabilidades. É importante lembrar que o resultado visual (fenótipo) muitas vezes esconde genes recessivos que podem pular uma geração.

The Genotypes Involved

For a horse to have the coat Paint Bay. it carries specific gene combinations. The possible genotypes for the sire include variants such as: E/e A/a To/n, E/e A/a To/To, E/e A/A To/n, E/e A/A To/To, E/E A/a To/n, E/E A/a To/To, E/E A/A To/n, E/E A/A To/To.

As for the dam, being Dun Dark Brown, may present in its DNA the alleles: E/e A/a D/n, E/e A/a D/D, E/e A/A D/n, E/e A/A D/D, E/E A/a D/n, E/E A/a D/D, E/E A/A D/n, E/E A/A D/D.

Understanding the Alleles

To understand the result of this crossing, note the gene sets at play:

Calculated Probabilities

Being the sire Paint Bay with genotype (E/e A/a To/n), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele (restriction) to 50% and the (a) allele (no restriction) to the other 50% and has a 50% chance of transmitting the Tobiano allele (To).

Being the sire Paint Bay with genotype (E/e A/a To/To), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele (restriction) to 50% and the (a) allele (no restriction) to the other 50% and always transmits the Tobiano allele (To).

Being the sire Paint Bay with genotype (E/e A/A To/n), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele to 100% of offspring, restricting black pigment to the extremities and has a 50% chance of transmitting the Tobiano allele (To).

Being the sire Paint Bay with genotype (E/e A/A To/To), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele to 100% of offspring, restricting black pigment to the extremities and always transmits the Tobiano allele (To).


Being the dam Dun Dark Brown with genotype (E/e A/a D/n), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele (restriction) to 50% and the (a) allele (no restriction) to the other 50% and has a 50% chance of transmitting the primitive Dun allele (D).

Being the dam Dun Dark Brown with genotype (E/e A/a D/D), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele (restriction) to 50% and the (a) allele (no restriction) to the other 50% and always transmits the primitive Dun allele (D).

Being the dam Dun Dark Brown with genotype (E/e A/A D/n), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele to 100% of offspring, restricting black pigment to the extremities and has a 50% chance of transmitting the primitive Dun allele (D).

Being the dam Dun Dark Brown with genotype (E/e A/A D/D), it transmits the (E) allele (black factor) to 50% and the (e) allele (red factor) to the other 50% and transmits the (A) allele to 100% of offspring, restricting black pigment to the extremities and always transmits the primitive Dun allele (D).

Based on a standard scenario, the statistical chances for foals from this crossing are:

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