Co-dominant vs Recessive Traits

Lets simplify this

Recessive genes are only expressed homozygous
Dominant genes are expressed the same if is homozygous or heterozygous
Co-dominant are expressed as heterozygous but have another expressed phenotype when homozygous


Epistasis is most defiantly at play.

Sounds like a pain to figure out if a trait is co, incomplete or dominant. And is there a list somewhere that has all the recessive, dominant, co-dominant, incomplete dominant traits?

Originally Posted by Blazing_Tiger

And is there a list somewhere that has all the recessive, dominant, co-dominant, incomplete dominant traits?

What species?

Cornsnake Morph Gallery
Ball Python Morph Gallery (very much incomplete)

In regards to co-dominant vs incomplete dominant, many morphs are misidentified as being co-dominant when they're in truth incomplete dominant.

Incomplete dominance and co-dominance are incredibly hard to distinguish, and in a lot of creatures look the same on the surface, and you can only tell on the microscopic level. Even that article you linked is misleading. A co-dominate flower for red and white will look the same as one with incomplete dominance more often that not.

I guess I did misspeak when I said all dominate alleles are co-dominate; Some can be strong enough to completely mask another genes expression.

I don't know if epistasis is a factor or not in snakes, but remember, it is not different alleles, but different genes. For the Labradors I mentioned, you look at 3 different genes total, writing the genotype as b/b;e/e;y/y where the b gene affects melanin amount, the e gene affects if they have the receptor to begin production of melanin, and y gene affects another pigment that is only noticed if melanin is not produced will make the coat either red or yellow.

Ok, I can't edit my above message, but after looking at that cornsnake morph gallery, the ones listed as double and triple recessive are most likely due to epistasis, in that they had to be recessive in multiple genes to have that morph expressed.

Originally Posted by Harlock

Incomplete dominance and co-dominance are incredibly hard to distinguish, and in a lot of creatures look the same on the surface, and you can only tell on the microscopic level. Even that article you linked is misleading. A co-dominate flower for red and white will look the same as one with incomplete dominance more often that not.

I guess I did misspeak when I said all dominate alleles are co-dominate; Some can be strong enough to completely mask another genes expression.

I don't know if epistasis is a factor or not in snakes, but remember, it is not different alleles, but different genes. For the Labradors I mentioned, you look at 3 different genes total, writing the genotype as b/b;e/e;y/y where the b gene affects melanin amount, the e gene affects if they have the receptor to begin production of melanin, and y gene affects another pigment that is only noticed if melanin is not produced will make the coat either red or yellow.

My article is not misleading. It is citing fact. I think you need to step away from the Labrador comparison, its adding to the confusion, very poor comparison with what the OP is asking. A single species of snake can have dozens of different mutations that can effect color and pattern (Ball Pythons and Cornsnakes being the top two), all using different modes of inheritance and physical expression.

Originally Posted by Harlock

Ok, I can't edit my above message, but after looking at that cornsnake morph gallery, the ones listed as double and triple recessive are most likely due to epistasis, in that they had to be recessive in multiple genes to have that morph expressed.

We don't use the terminology "epistasis," you are just causing more confusion. When more then one morph is expressed it's simply called a combination. It clearly states what makes up each one of those combination morphs on each individual page.



Travis, I noticed something else with your initial post...

Super Pastel x Albino = Pastels het Albino

This is because you're breeding Homozygous Incomplete Dominant to Homozygous Recessive. To produce Super Pastels that are het Albino, both parents must be expressing Pastel in some way (whether Pastel or Super Pastel).

Piebald x Piebald = Piebalds

This is because you are breeding Homozygous Recessive to Homozygous Recessive.

@Scott - Although some parts were mildly confusing (due mainly to my ignorance in the subject), you did help me understand a good bit. And thank you.

@Stephanie - The links were very helpful and i know they will be useful! It really seems like you know your stuff! Thanks for all your help. And if you don't have an issue with it, you mind being my go-to geneticist haha? It will be long before i start breeding though.

Originally Posted by Blazing_Tiger

@Stephanie - The links were very helpful and i know they will be useful! It really seems like you know your stuff! Thanks for all your help. And if you don't have an issue with it, you mind being my go-to geneticist haha? It will be long before i start breeding though.

I got into genetics because I feel in love with the large variety of inheritable traits and combination's in Cornsnakes. Disgustingly enough, you can name a Cornsnake pairing and I can spit out the results from memory. Ball Pythons I can get about 2/3 right without assistance, they have way too many trade names.

Something to short cut your Ball Python morph troubles...This link has a wizard that automatically calculates pairings.

Haha thats so cool (the morph wizard, and that you can name the results from memory). Im guessing you have been breeding corns for awhile then huh? I'm looking at getting a corn soon in May. Only 5 weeks left of college (wow that sounds nice). I'm really looking for any age below 1.5 yrs. I seen on your website that you will be having some corns available soon. Whats pricing like for your corns? And im only a 1 hour drive away from hanover what would shipping cost? This will be my first corn, but i have been doing my research.

Originally Posted by Blazing_Tiger

Haha thats so cool (the morph wizard, and that you can name the results from memory). Im guessing you have been breeding corns for awhile then huh? I'm looking at getting a corn soon in May. Only 5 weeks left of college (wow that sounds nice). I'm really looking for any age below 1.5 yrs. I seen on your website that you will be having some corns available soon. Whats pricing like for your corns? And im only a 1 hour drive away from hanover what would shipping cost? This will be my first corn, but i have been doing my research.

I'm going to PM you with information on my Cornsnakes. I'll get kicked in the butt by a mod if I post it here.

I'm in Lancaster frequently, so if you do see something you like, I can always meet you up at TFP or somewhere else up that way.