Genetics
(c) Gryph- if you repost this article, please post with a link back to my website.
Color genetics is a very important subject in breeding rabbits. Understanding how genetics works and the gene sets within rabbits will assist you in obtaining the colors and patterns you desire. Having a good understanding of color genetics can open up a whole new world of breeding for you. It will cut the restraints when breeding for type. If you understand what colors and patterns your rabbits are hiding then you can feel much freer in selecting your breeding pairs. Understanding how colors work together can allow you to cull for type, instead of tossing away that marvelously typed rabbit simply because it is an unrecognized color.
Understanding rabbit color genetics can be critical to a successful breeding program. The idea of genetics, genotypes, phenotypes, and so on can be daunting but it doesn’t have to be. By learning even the basics you can open up your breeding program to almost unlimited variations of color and pattern. There are over 200 possible genotypes based on the 5 main color genes. That means LOTS of colors to play with! Genotypes are the same across the board regardless of the breed of your rabbit. Jersey Woolies and Flemish Giants use the exact same genotypes.
Before you start playing with colors, however, make sure you study the SOP for your breed if you plan to show or breed for show, because in some breeds only certain varieties are recognized. If you are more interested in pelts or meat or just breeding for pets, then you have a little more freedom in your breeding program.
When studying genetics you will often here some very unfamiliar words. Words get further confused when they are incorrectly used on a web site. It is important that you understand certain words related to genetics in order to correctly apply what you know about your rabbits and be able to predict future offspring. Below are some common genetics words and their definition. We have tried to put them into everyday language so you can understand what they are and how they relate to your rabbits. For the purpose of giving us an understanding of how genetics terms works we’ll be referring to the A Locus (or set) of the rabbit. This is also known as the Agouti pattern locus. Three genes or alleles make up this locus, A (agouti), at(tan) and a(self).
Locus/Allele
Locus: The location of certain genes on a chromosome is the technical definition of this word. To make it simple though, you can refer to it as the set of genes that makes up a particular characteristic. So for rabbit color there are five major Loci (plural for Locus) that make up the color of the rabbit: A, B, C, D, E. The A locus refers to the agouti hair pattern.
Allele: Each Locus of the rabbit is made up of several possible genes, each of these is known as an allele. For the A locus there are three possible alleles as mentioned above A, at and a. They will always be present in any combination of two. When the parent has an offspring it will pass on one of the two alleles to itself offspring.
Dominant/Recessive
Dominant: This would be the stronger of the genes. It will always be seen in the rabbit if it is present.
Recessive: This would be the weaker of the genes. If a more dominant gene is present this gene can be carried but will not be seen in the rabbit.
When you look at a rabbit, there is a color you see and a completely different color that you don’t. The color you see is dominant (visible) and the color you can’t see is recessive (hidden). There’s a great example that is used to explain recessives and dominants using Agouti, Tan and Self patterns (these are fur patterns not colors).
Picture these three patterns as people. The front person is large and round, representing Agouti. Next we have the middle center who has a medium build, representing Tan. Last we have a skinny person representing Self. If the large person (Agouti) is standing in front of us, we wouldn’t know who was hiding behind him. It could be a medium person (Tan) or a skinny person (Self), or he could have another large person. We don’t know which; we just know that because this person is large he can easily hide someone equal or smaller behind him. Next we have the medium guy (Tan). He can’t hide a large person behind him- we’d see a large person trying to hide behind him. But he could hide another medium person or a skinny person, right? That means your Tan rabbit can either have another Tan or a Self hidden. Finally we have the skinny guy (Self). No one can hide behind him except another skinny person.
In the A gene set, A (agouti) is most dominant, followed by at (tan) which is recessive to A (agouti) but dominant over a (self). The non dominant gene or recessive gene is the (self) gene. Let’s look at the possible alleles from above and determine the appearance.
Genotype/Phenotype
Genotype: All those letters that tell us what the rabbit will look like. For example a black rabbit might be something like this aaBBCCDDEE.
Phenotype: What the rabbit appears to us. In the example above: black.
Heterogeneous/Homogeneous
Heterogeneous: The two genes in the allele are not the same. As an example: Aa or Aat
Homogeneous: The two genes in the allele are the same. As an example: AA or aa
Punnett Square
Punnett Square: A tool used by British geneticist Reginald Punnett to predict the likelihood of an offspring having a particular genotype.
Understanding rabbit color genetics can be critical to a successful breeding program. The idea of genetics, genotypes, phenotypes, and so on can be daunting but it doesn’t have to be. By learning even the basics you can open up your breeding program to almost unlimited variations of color and pattern. There are over 200 possible genotypes based on the 5 main color genes. That means LOTS of colors to play with! Genotypes are the same across the board regardless of the breed of your rabbit. Jersey Woolies and Flemish Giants use the exact same genotypes.
Before you start playing with colors, however, make sure you study the SOP for your breed if you plan to show or breed for show, because in some breeds only certain varieties are recognized. If you are more interested in pelts or meat or just breeding for pets, then you have a little more freedom in your breeding program.
When studying genetics you will often here some very unfamiliar words. Words get further confused when they are incorrectly used on a web site. It is important that you understand certain words related to genetics in order to correctly apply what you know about your rabbits and be able to predict future offspring. Below are some common genetics words and their definition. We have tried to put them into everyday language so you can understand what they are and how they relate to your rabbits. For the purpose of giving us an understanding of how genetics terms works we’ll be referring to the A Locus (or set) of the rabbit. This is also known as the Agouti pattern locus. Three genes or alleles make up this locus, A (agouti), at(tan) and a(self).
Locus/Allele
Locus: The location of certain genes on a chromosome is the technical definition of this word. To make it simple though, you can refer to it as the set of genes that makes up a particular characteristic. So for rabbit color there are five major Loci (plural for Locus) that make up the color of the rabbit: A, B, C, D, E. The A locus refers to the agouti hair pattern.
Allele: Each Locus of the rabbit is made up of several possible genes, each of these is known as an allele. For the A locus there are three possible alleles as mentioned above A, at and a. They will always be present in any combination of two. When the parent has an offspring it will pass on one of the two alleles to itself offspring.
Dominant/Recessive
Dominant: This would be the stronger of the genes. It will always be seen in the rabbit if it is present.
Recessive: This would be the weaker of the genes. If a more dominant gene is present this gene can be carried but will not be seen in the rabbit.
When you look at a rabbit, there is a color you see and a completely different color that you don’t. The color you see is dominant (visible) and the color you can’t see is recessive (hidden). There’s a great example that is used to explain recessives and dominants using Agouti, Tan and Self patterns (these are fur patterns not colors).
Picture these three patterns as people. The front person is large and round, representing Agouti. Next we have the middle center who has a medium build, representing Tan. Last we have a skinny person representing Self. If the large person (Agouti) is standing in front of us, we wouldn’t know who was hiding behind him. It could be a medium person (Tan) or a skinny person (Self), or he could have another large person. We don’t know which; we just know that because this person is large he can easily hide someone equal or smaller behind him. Next we have the medium guy (Tan). He can’t hide a large person behind him- we’d see a large person trying to hide behind him. But he could hide another medium person or a skinny person, right? That means your Tan rabbit can either have another Tan or a Self hidden. Finally we have the skinny guy (Self). No one can hide behind him except another skinny person.
In the A gene set, A (agouti) is most dominant, followed by at (tan) which is recessive to A (agouti) but dominant over a (self). The non dominant gene or recessive gene is the (self) gene. Let’s look at the possible alleles from above and determine the appearance.
- AA- Agouti
- Aat- Agouti carrying the tan gene, because agouti is dominant
- Aa- Agouti carrying the self gene, because agouti is dominant
- atat- Tan
- ata- Tan carrying the self gene, because tan is dominant
- aa- Self
Genotype/Phenotype
Genotype: All those letters that tell us what the rabbit will look like. For example a black rabbit might be something like this aaBBCCDDEE.
Phenotype: What the rabbit appears to us. In the example above: black.
Heterogeneous/Homogeneous
Heterogeneous: The two genes in the allele are not the same. As an example: Aa or Aat
Homogeneous: The two genes in the allele are the same. As an example: AA or aa
Punnett Square
Punnett Square: A tool used by British geneticist Reginald Punnett to predict the likelihood of an offspring having a particular genotype.
