Co-dominant vs Recessive Traits

Today was the first day i started trying to learn about genetics for breeding animals. I think i have the basics down. Let me know if i'm right.

1. Is a co-dominant trait just a "dominant recessive trait"? as oxymoron as that sounds? As in, a co-dominant trait is just a recessive trait that is visible?

2. What if you have homozygous recessive trait albino (aa), and cross it with a Super pastel(p*p*)? Will the offspring, according to punnett square, be 100% Super Pastel het for Albino?

3. Well, i know with co-dominant traits you can make supers. According to New England Reptile "Piebald" is a recessive trait in ball pythons. So what if you would cross a Piebald(pp) x Piebald(pp). Would you create a Super Piebald? Or is there something genetically with recessive alleles so that the offspring would just be Piebalds(pp)?

Thats all for now! But i'm sure ill have some more questions soon depending on how much time i have to expand my genetics knowledge.

Thanks for any help,

Travis Stewart

PS: I would like to hear from YOU guys! I've already looked at the New England Reptiles genetics pages(101,201,301), along with a the first three(101,201,301)VMSherps genetic pages. But if you know of any other sites that explain genetics better, they would be appreciated!

You're a bit off with co-dominance. Essentially, a recessive trait will only be shown if it is the only genes an animal has. A co-dominate trait will show, even if another dominate trait is inherited.

Example: Human blood groups: 'A' and 'B' are co-dominate, while 'O' is recessive. If I get an 'A' or a 'B' from either parent, I will show that blood group, and if I get an 'O' as well, the 'O' will be hidden. If I get both 'A' and 'B' then my blood type will be 'AB' as both genes get expressed.

2. For this cross, yes every single offspring would be p*a.

3. No. Recessive is recessive. You would need two of the recessive alleles to even show this trait (baring other things like epistasis, which I don't feel like typing up)

Okay. So the order of Dominance is:Co-Dominant, Dominant, Recessive? Where Co-Dominant trait will show over a Dominant trait, and a Dominant trait will show over recessive trait?

Also, is it true to say that Super Pastel could be thought of as Pure Pastel and/or 100% Pastel? Where as an animal with a Dominant trait and the co-dominant trait pastel is only 50% pastel and 50% dominant trait? Or does the dominant trait not show at all in the pastel? If the dominant trait doesn't show at all, then why do Super Pastels look different then Pastels?

If my way of thinking doesn't make sense to you, i completely understand! I have a way with losing people. Maybe i word it in a way that only i understand? i don't know. But if you need anything clarified, i would be happy to.

And again, i am pretty new to genetics and how they work so please excuse me if my ignorance frustrates you in any way.

So, I think you are separating co-dominate and dominate traits. They are the same thing. If you have multiple dominate alleles, then they are co-dominate. Both get expressed to some extent, and are shown in an individual.

So yes, a super pastel would be a pure pastel.

Now, the thing is, this is a very simplified start to genetics. Epistasis (which I mentioned earlier) is where a third gene has a factor in the expression of other ones; the most common example is in Labrador coat colour. (A dominate allele in one trait allows for black and chocolate in that it codes for a receptor of melanin, where if you have two recessive (mutations), then the gene for yellow/red coats will be expressed.

Oh ok. I guess i got confused with what exactly co-dominant alleles were. It just means that both alleles in the gene are dominant?

Yes, it can be pretty easy to mix up terms, so don't worry about it.

Alright cool. Thanks a lot. And i figured there was something more to genetics then what i was learning. But overall for 1 day of reading about it, i think i did pretty good at understanding it. And thanks for your help Scott, i really appreciate it.

And this is probably going to sound like a dumb question but does Epistasis pertain to breeding snakes also? Or is it generally not used in snake breeding?

Not sure on that, I don't breed snakes but I like genetics.

Interesting fact, a silkworm's silk glands have about half a million chromosome sets.

So could any snake breeders out there tell me if what i seem to understand about snake genetics is all there is to it? Or is there something else i would have to know as a snake breeder?

@Scott - If you feel like it, send me a PM explaining that interesting fact of yours. Besides what i said in this thread, i'm clueless when it comes to genetics.

Originally Posted by Harlock

So, I think you are separating co-dominate and dominate traits. They are the same thing. If you have multiple dominate alleles, then they are co-dominate. Both get expressed to some extent, and are shown in an individual.

That's not correct. They are not the same thing in the least.

Travis, take a look at this article. Toward the end of the article it discusses the different modes of inheritance, how they work and how to prove it out.