Gene Types


Most Ball Pythons fall under different types of genetics. This is a must to learn and understand what will come out when you breed your ball pythons.


This is the end form or the last step of a morph. A Dominant gene has no “Super” that can be made by breeding it back to the same morph. For example, if you breed a Spider to a Spider, you only make Spiders. There is no Super Spider and that makes Spider a Dominant gene. Examples of Dominant genes are: Spider, Pinstripe, Blue and Black Eye Lucy and Ivory to name a few.


This is where a morph can breed with the same morph type and produce a “Super” of itself. For example, if you breed a Pastel to a Pastel, Then you would make a Super Pastel. Examples of Co-Dominant genes are: Pastel, Cinnamon, Lesser, Mojave, and Yellow Belly to name a few.


Now this is where things can become tricky when understanding the outcome of breeding two snakes together. In simple terms, you need both mom and dad to carry the same recessive trait to produce that visual morph. This differs from co-Dominant and Dominant where you only need one parent to pass the gene into the babies.

Recessive Hets

If you have done any looking around on the internet classifieds of ball pythons, you have come across people selling hets. Het simply means that the snake carries the gene, but is hidden and looks just like a normal. Now you also may have seen different percents listed with the Het such as 50%, 66%, or 100%. I will cover later on how we get these percents, but each percent is your odds of carrying the gene. It should be clear that 100% is what you prefer when buying a het snake. The lower percents are sometimes confused by thinking that’s how much of the gene they carry. That is not the case. Each snake either carries the entire gene, or no gene at all. This percent is the odds of the snake having the gene. Still confused? Don’t worry, we will talk more on this soon.


New types of ball pythons are still being discovered. This makes this industry exciting because anyone new to ball pythons could produce a snake that the world has never seen. The more you research, go to trade shows, and talk with fellow breeders, you will learn that not all snakes have a proven track history when breeding. For the beginners, start simple and stick with the common genes. As your collection grows, so will your desire to branch out and have fun with uncommon projects.


Now it’s time to understand what your chances are when you put two different, or two of the same snakes together. Now back in 6th grade, I was passing notes, sleeping, or asking the teacher, “When will we ever use this garbage?” What I missed in class was the lesson on genetics and the “Punnett Square”. For all those who were not paying attention in class, it’s time to get a refresher course.

Breeding Co-Dominant and/or Dominant Genes

The Punnett Square will give you the odds and possible outcome of babies. Remember, just cause the Punnett Square says one thing, Mother Nature has the ultimate control. Unlike other reptiles, we cannot control sex, color, or morph by changing incubation temperatures or conditions of the eggs. Let’s get started with a simple breeding. For our first example, let’s say you breed your Spider male to a normal female. It will not matter which parent carries the gene, it will still work the same.

At the top of the square, we will place the genes of the father. For our example we stated he was a Spider. To complete the square we will need to list every gene that can be produced by the Spider and that also includes normal.


To the left, we will place the genes that make up a normal and that is only a normal. Now we fill in each side and top into the square. You can now see that you have a 50% chance of getting Spiders and 50% chance of getting normals if you breed them together. When working with Dom and Co-Dom snakes, the same outcome will happen if you breed Pastel, Spider, Pinstripe, etc.

 Now lets say your breeding a Pastel to a Spider because you want a Bumble Bee. Using the same square, lets see the odds of what we will make. 


We have placed the Spider on top and the Pastel on the side. must place every gene that makes up the morph. The normal gene is present in both of these morphs. That includes all Co-Dom and Dom ball pythons as well. This rule does not apply when we get into recessive. From the outcome of the square, you have a 25% chance of getting each a Normal, Pastel, Spider, and Bumble Bee. 

 For my last example we are going to use a double morph male Bumble Bee and breed it to a female Bumble Bee. For single morphs we could you the 4 square box. As we increase the morphs, we must increase the square. Lets start by placing all the genes that are made up of a Bumble Bee. Because this example is using two Bumble Bees, each of them will be across the top and side. 


Part of learning is knowing what the outcome of each morph would be. This may look confusing at first glance, but the more you learn your genetics, the easier it will be to create your own square using your own ball pythons. Now let’s see what the odds of producing each snake from the example:

1/16 Chance of making a Normal

1/16 Super Pastel

2/16 Pastel

3/16 Spider

6/16 Bumble Bee

3/16 Killer Bee (Super Pastel Spider)

As you can see, you still have a slight chance of producing a normal. When first learning, start small and practice making different squares with different snakes. The more practice.....the better you become.

Breeding Recessive Genes

Before getting to this, make sure you have a complete understanding of what we just covered. This next part can and will be a lot more confusing to the person learning genetics.

To make this simple, each parent must carry the gene either Het or Visual to reproduce a visual baby. Unlike Co-Dom or Dom genes where only one parent is needed to pass the gene to the offspring. Listed below is the outcome of breeding recessive snakes. For the example, we are going to use a pied breeding.

Pied to Pied = All Visual Pieds

Pied to Het Pied =  1 in 2 - Visual Pieds

                                     1 in 2 - 100% Het Pieds

Pied to Normal = All 100% Het Pieds

Het Pied to Het Pied = 1 in 4 - Visual Pieds

                            1 in 4 - Normal

                                          2 in 4 - 100% Het Pieds

Because we are unable to tell which 2 of the 3 are Het Pied, all the babies are considered to be 66% chance of being Het Pied. This is where the 66% comes from.

Het Pied to Normal = 2 in 4 - 100% Het Pied

                      2 in 4 - Normal

Because we are unable to tell which half of the babies are Het Pied, all the babies are considered to be 50% chance of being Het Pied. This is where the 50% comes from.

As you can see from the above breeding, anytime you breed a visual recessive, all the normal looking babies will be 100% Het for the gene. Of course you can mix your recessive with Co-Dom and Dom genes and get Hets that you would breed back to the Visual to produce the double morph.

I hope this has helped get you started on understanding the genetics of snake breeding. Keep practicing and learning as that will be the key to making great snakes. You may contact me anytime if you have further questions or would like help in understanding your next breeding project.