This is my first time posting on here, so I hope this is the right place I love the adorable Gongylophis colubrinus and am curious about the genetics of the “snow” morph: What causes the super-light coloring and black eyes? Is it related to anerythristic genes? I see a morphology page and listings on here for albino KSBs, but they all seem more similar to a wild type’s coloration and do not have the same anery/black eyes. Basically, I’m just asking how snows are produced and why they look the way they do.
I’m a first-year bio major, so I don’t have the BEST understanding of genetics, but hopefully I can pick up the basic concepts if someone wouldn’t mind explaining! No pressure to anyone to respond, obviously, I’d just be grateful. Thanks so much.
Welcome to the community! Snow Kenyan Sand Boas are a combination of the albino mutation and the anerythristic mutation. Meaning it is homozygous for albino as well as homozygous for anerythristic since both of these mutations are recessive. The anerythristic mutation is what gives it the black eyes.
Thank you so much for your response!
This may be a silly or convoluted question, so feel free to disregard it, but because they have those two homozygous traits, does that mean that a Snow is not considered “het” for the albino or anery traits, because it will always produce albino or anery offspring? Or can they also produce other snows…? Sorry, I hope I don’t sound too clueless, I know that both anery and albino are recessive, but the hetero/homozygous stuff still throws me off sometimes when it comes to snake morphs/real-world application LOL. ty
A snow is not considered heterozygous (“het”) for anery or albino as it is homozygous for both traits. It will always pass along one copy of each mutation through sexual reproduction, albino and anery, but because these mutations are recessive this does not mean that the offspring will always be visually albino and/or anery. It will depend on the other parent’s genetics as to what the offspring will consist of. In sexually reproducing species like Kenyan Sand Boas, the offspring receive one copy of the gene from each parent. Since it takes two copies to express a recessive gene, that means that you will need to know the other parent’s genetics to determine what the offspring will consist of.
If the snow parent is bred to a snow, all snows will be produced since each parent will always pass along one copy of albino and one copy of anery, meaning the offspring will each receive two copies of albino (homozygous) and two copies of anery (homozygous). Being homozygous for each of these mutations, both will be visually expressed and therefore all will visually be snows.
If the snow parent is bred to a normal that is not het for either mutation, all “double hets” will be produced. Since each parent passes along one copy of a given gene, the snow parent will pass along one copy of the albino and one copy of the anery to the offspring while the normal parent will pass along one copy of the “normal” in each instance. The double het offspring will all appear normal but carry the genetic materials to produce each mutation through sexual reproduction when paired with the right mate.
Here is a pretty cool calculator tool to play around with that MorphMarket provides. You can plug in different parent genetics to see the possible offspring.
Sand Boa Genetic Calculator
Adding that I am not a geneticist by trade so this description is in layman’s terms.
Wow, I cannot thank you enough for such a comprehensive response; I greatly appreciate it. The genetics calculator is something that I’ve been honestly obsessed with lately (such a neat feature!) but I wasn’t sure exactly how the “Snow” morphs fit into the available traits, so your replies have been so helpful. I love this incredible little species and am so glad to have a better understanding of their visual traits, both as a student and a hobbyist. Thanks so much, again!
Have a lovely week