Reptile & Amphibian Forums

I am still new to the ball python breeding world but I am trying to understand gentics more, I feel like I have a good had on simple res. gens, and co-dom and dom. Where I am lost is res. with a co-dom, for example how do you make a putnet square for a pastel clown with a clown, pastel clown, or super pastel clown? I am also a little lost with the double co-dom, such as what you get when you cross the bumble bee with a normal, pastel, super pastel, or killer bee?

If any one could help me understand these better I will love any recommended resorces and or links. I have read the compleat ball python's secton on genetics several times but I am still lost.

thanks,
matt

when you do the punnet square for a pastel...treat it like a het...Aa will be a Pastel....aa will be a super pastel. Because that is what it is a het...just a visiual het...as for the "dominant" genes. The spider has as of yet to have a super proven to my knowledge...I am sure people have tried...it very weel could be lethal so every spider that reproduces should produce 50% ratio so you will always treat it like a het.

You know how to do the di-hybrid cross?
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Michael Enriquez

I am not sure what di-hybrid crossing is, but if it is filling out the punet square I do know how to do that my biggest problem is knowing how to break up the gentics into the sectons for the side of the square after that reading the square is easy. For example if I were to breed a Pastel Clown to a Pastel Clown. I know I would have a normal Pastel gene: (Pp) and I would have a hom Clown-for the clown trait to show it has to be hom. from what I have read- (CC)Then I would assume that you could have a possiblity of hets in the coding as well (Cc)Then would the other gene be just a normal broken off of the Pastel?

I think my biggest problem in the gentics is how to break the parents gentics, I also get confused as to how one parent pass 2 gens in to the egg, such as seen in the bumble bee breeding to normal.

When you are dealing with double, triple etc mutations, just do a separate punnet square for each mutation and then multiply the results together to figure out the offspring. Ex. a pastel clown bred to a clown: Clown x clown results in 100% clowns. Pastel x wt results in 50% pastel and 50% wt. Therefore a pastel clown x clown should result in 50% clowns and 50% pastel clowns.

Ppcc would be the genotype you are dealing with

2 in fact

so the left side would have 4 possibilities and the top would have 4 possibilities.

Pc
Pc
pc
pc

every sperm or egg produced will be 1 of those 4 possibilities.

then just bringthem accross and bring them down...match up the alleles and you got it...do a search for a dihybrid cross and you will likely see an example.
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Michael Enriquez

So thats the long drag out way, that can be reduced because, you actually only have 2 different gamette possibilities in egg and sperm; Pc and pc, the square for that cross is
Pc pc

Pc

pc

so 1/4 super pastel clown, 1/2 pastel clown, 1/4 clown.
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Jeff Benfer

1.0 pastel Python regius
1.1 mojave Python regius
0.1 normal Python regius
1.3 Terrapene carolina thriunguis
2.3 Terrapene carolina carolina
4.1 Kinosternon baurii
1.1 Malaclemys terrapin terrapin
2.2 double het albino and anerythristicThamnophis sirtalis parietalis
1.0 anerythristic Thamnophis sirtalis parietalis
2.2 Iowa snow Thamnophis radix
0.2 het Christmas albino Thamnophis radix
1.1 double het cherry erythristic, albino Thamnophis sirtalis sirtalis
1.1 melanistic Thamnophis sirtalis sirtalis
1.1 triple heterozygous for amelanistic,carmel, and stripe Pantherophis guttatus
0.1 anerythristic motley Pantherophis guttatus
0.1 Okeetee Pantherophis guttatus

How come you can not get a super pastel in the mix??

You will need to do some homework, and there are some basic rules for lettering, capital vs lower case depition, ect, ect. But let me give you this basic tip that is fundemental in understanding multiple gene punnet squares; above the square you are listing all the gamete possibilties of one of the parents, and on the left side you will list all the gamete possibilties of the other parent, then fill in respective boxes by combining the two respective gamete possibilty, whether recessive or dominant, this process of solving for the genotypes is the same, what does change is how a genotype in one of the boxes will be expressed phenotypically. So to sum up is a four step process; 1. fugure out what are the gamete possibilities from each parent, 2. solve for the genotype possibilities, 3. figure out what the phenotype will be for the respective resulting genotypes based on the relationships of recessive, co-dom, dom. 4.From that you can then tally up the similar phenotype boxes and predict the ratios and probablility of the offspring of the considered breeding. Keep this in mind and the only limit to the number and types of gene combos you can solve for is the size of the piece of paper. Hope this will help, best of luck.
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Jeff Benfer

1.0 pastel Python regius
1.1 mojave Python regius
0.1 normal Python regius
1.3 Terrapene carolina thriunguis
2.3 Terrapene carolina carolina
4.1 Kinosternon baurii
1.1 Malaclemys terrapin terrapin
2.2 double het albino and anerythristicThamnophis sirtalis parietalis
1.0 anerythristic Thamnophis sirtalis parietalis
2.2 Iowa snow Thamnophis radix
0.2 het Christmas albino Thamnophis radix
1.1 double het cherry erythristic, albino Thamnophis sirtalis sirtalis
1.1 melanistic Thamnophis sirtalis sirtalis
1.1 triple heterozygous for amelanistic,carmel, and stripe Pantherophis guttatus
0.1 anerythristic motley Pantherophis guttatus
0.1 Okeetee Pantherophis guttatus

Blue Genes web site:
http://www.animalgenome.org/edu/genetics/main.html

Genetics for Herpers:
http://cornguide.com/genetics.php

Paul Hollander