Reptile & Amphibian Forums

I have been looking around in some old genetics text books and on line but can't really get a handle on what exactly is meant by co-dominance of a trait as it relates to P.c.c. pattern (stripped vs. blotched). Most of the references seem to focus on human blood type examples......

Is there anyone out there you can help me out.... Can two blotched parents produce striped offspring? What results from a pairing of a blotched individual and a striped individual?

Thanks in advance...........

ginter

John-
In my understanding, this doesn't appear to be a co-dominant trait. In co-dominance, the phenotype of both alleles are expressed in the heterozygote. I do not have a great understanding of the striped catenifer, but if it were to be codominant, you would expect to see three different phenotypes for the striped gene. This is because neither allele is dominant over the other and heterozygotes show both phenotypes. If wildtype is represented by the letter A and striped is represented by the letter B, than you would see a banded animal for AA, the heterozygous (AB) animals would have another phenotype, and the BB homozygous dominant animals would be striped (ex. normal, matrix, and ivory blood pythons). As far as I know, the striped catenifer do not have this phenotypically different heterozygous condition (AB). I would think that this inheritance would be more similar to complete dominance. If you have any more information on the striped gene, let me know and maybe I can try to explain the possibilities better.

Ian

I am with you on that . That is what was giving me trouble with the concept as I know there only two phenotypes but I could swear I have heard a few folks here on the forum suggesting that the difference between striped catenifer and striped annectans is that the trait is "codominant" in catenifer......

Thanks for you assitance

ginter

Hi John,

While you have those text books open read about incomplete dominance. Most reptile traits described as codominant are actually examples of incomplete dominance.

I have no idea how this related to catenifer, however.

The little catenifer you sent are doing great. Both have eaten a second meal.

Glad to hear that the pumilus are doing well. They are the smallest things I hatch out so I tend to be a bit more worried about them although they always seem to do well.

Thanks for the tip on incomplete dominance....... I will check that out.

Unless I am missing something, it doesn't appear that it is a case of incomplete dominance either. Incomplete dominance should also display three phenotypes, although differently than codominance. The common example of incomplete dominance is in four o'clock flowers. The homozygous recessive genotype is expressed as a white flower while the homozygous dominant form is expressed as a red flower. The heterozygous condition is an intermediate, being expressed as a pink phenotype. This is because in the homozygous recessive condition (cc) a protein is not produced for color (no pigment = white color) and the homozygous dominant condition (CC) (both alleles code for red pigment production= red color). The intermediate heterozygote (Cc) only has one allele coding for red pigment production (C) while the recessive allele (c) codes for no production and you get a pink coloration. As there doesn't seem to be an intermediate phenotype in catenifer, I think that this is likely not a case of incomplete dominance.

I'm not saying it is. What I am saying is that if one is reading about codominance in order to understand how it relates to reptiles they'd be better off reading about incomplete dominance.
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Currently keeping:

3.5.5 Gonyosoma oxycephalum (Javan, mixed colors)
0.0.3 Rhynchophis boulengeri
0.2 Lampropeltis triangulum multistriata
0.2 Lampropeltis triangulum gaigeae
0.0.3 Rhamphiophis rubropunctatus
1.1.1 Morelia viridis (Aru & Merauke locale types)
1.0 Morelia clastolepis
1.0 Rhodesian Ridgeback

I agree, no offense intended, was just explaining why I don't think it is the case (I may be wrong). Hopefully someone can chime in with more info on the phenotypes with this mutation. Once again, I meant no offense with my post, just talking it through in case people don't know the background on that type of inheritance.

Ian

I read this in a post a few weeks ago thus my confusion....

"I hear what your saying. Alot people dont care and mix the two together. I have allways been careful and never mixed the two speices.
Here is comparison shot. San Diegos tend to have bolder strips and background patterns where the Pacicfic are more speckled. Another note is San Diego's stripping gene is simple recessive and the Pacific's stripping gene is co-dominate."

With that said I guess my question is this---has anyone bred striped to blotched individuals? If so what was the out come w/ regards to patterning of hatchlings?????

I am a couple of years away from getting the answer for myself so if anyone has already done this let me know....

Thanks for all the input.

ginter