Basic Genetics

Sorry, I know this is probably a overly asked question on this forum, but i am new to the whole BP world. Ive had my normal girl for about 4 months now and i am about to purchase a pastel male mojave. what are the possible outcomes of a clutch when paired together?

Pastel Mojave x Normal =

1/4 Normal

1/4 Pastel

1/4 Mojave

1/4 Pastel Mojave (aka Pastave)

http://www.worldofballpythons.com/wi...=73,32&female=

sweet i actually figured that right. i wasnt sure if I was right. Thanks

The best place I've found on the net to learn about genetics is:
http://vmsherp.com/LearningCenter.htm

And for determining clutch out comes is on owal reptiles genetic calculator. I don't have that one saved on my phone but think you can find it on owalreptiles.com and world of ball pythons has one too. Here's the link:

http://www.worldofballpythons.com/wizard/

Hope that helps.

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Originally Posted by H.o.F.R

The best place I've found on the net to learn about genetics is:
http://vmsherp.com/LearningCenter.htm

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I looked at that site and abandoned it at the end of the third paragraph in the Genetics 101 file. There were so many mistakes that it wasn't worth going on further. The guy obviously put a lot of work in it, but I don't think he spent much time reading a genetics text. Too bad. :(

We have a sticky in this very forum that gives a great "BP Genetics 101": http://ball-pythons.net/forums/showt...Basic-Genetics

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Originally Posted by Annarose15

We have a sticky in this very forum that gives a great "BP Genetics 101": http://ball-pythons.net/forums/showt...Basic-Genetics

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Another genetics page whose author spent insufficient time reading a genetics text. :(

The best herp genetics web page I know of is http://www.serpwidgets.com/main/genetics01

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Originally Posted by paulh

Another genetics page whose author spent insufficient time reading a genetics text. :(

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Well Paul, I disagree.

I think Judy's lesson in basic genetics is pretty darn good. I think it does a great job of explaining the basic terms used and also helps people new to genetics understand how the hereditary genes for Ball Pythons behave.

My major beef is that all the graphics are wrong. They show pairs of genes in a single DNA molecule. In reality, each member of a gene pair is in a different DNA molecule. The two DNA molecules are in different chromosomes.

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Originally Posted by paulh

My major beef is that all the graphics are wrong. They show pairs of genes in a single DNA molecule. In reality, each member of a gene pair is in a different DNA molecule. The two DNA molecules are in different chromosomes.

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assuming for the sake of argument that you are more qualified than others to pontificate on genetics, the point is that these are basic lessons to assist those unfamiliar with a working knowledge. i.e. people like me. I hadn't done a punnet square or considered recessive genetics since AP biology until I started keeping snakes. these kinds of resources are extremely useful as a starting point. why do you feel the need to condescend in multiple threads on the subject?

I've had a University course in genetics and several years working in a genetics lab helping pro geneticists with their projects. So I am more qualified than many on this forum.

Shouldn't a blind person be warned when he is walking towards a patch of quicksand?

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Originally Posted by paulh

I've had a University course in genetics and several years working in a genetics lab helping pro geneticists with their projects. So I am more qualified than many on this forum.

Shouldn't a blind person be warned when he is walking towards a patch of quicksand?

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So, one college class and "several" years being a lab tech? Although I respect everyone's right to respectively express their opinions, where is the work you have done or published in herpetology, or ball pythons, specifically? And isn't quicksand a bit of an extreme analogy for a basic understanding of what you get when you breed snake "w" to snake "z"? My undergraduate degree was in exotic preveterinary medicine, I spent six years working in clinics, and I have owned snakes for 26 years. Where do I stand on your scale? Show a little respect for the time and effort Judy has spent learning and compiling the information that she shares with us regularly.

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Originally Posted by paulh

I've had a University course in genetics and several years working in a genetics lab helping pro geneticists with their projects. So I am more qualified than many on this forum.

Shouldn't a blind person be warned when he is walking towards a patch of quicksand?

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When is anyone in this hobby going to be walking into your metaphorical quicksand? The concept of inheritance is there

I can try for a metaphor, when someone asks how to put gas in their car, do you tell them how the internal combustion engine works? Most people are happy knowing just how to put gas in their car and use terms like regular gas and premium gas.

also I believe the term codominant is misused in the link you posted.

Quicksand is a bit over the top. Mud hole would be a better comparison.

I have published no papers on ball pythons. A couple of years ago I was coauthor on a paper on the genetics of zebra finches. http://papers.ssrn.com/sol3/papers.c...act_id=1746843

If someone asks how a car's internal combustion engine works, do you tell them that water goes in the front of the car and gas in the back and both go in the engine? While true, it gives the impression that water and gas mix in the engine, which is false.

"Codominant" in the link gets over the concept that two genes, A and a, produce three gene pairs, AA, Aa, and aa. Genotype AA produces phenotype 1, genotype Aa produces phenotype 2, and genotype aa produces phenotype 3. What else does a breeder need to know about codominance?

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Originally Posted by paulh

Quicksand is a bit over the top. Mud hole would be a better comparison.

I have published no papers on ball pythons. A couple of years ago I was coauthor on a paper on the genetics of zebra finches. http://papers.ssrn.com/sol3/papers.c...act_id=1746843

If someone asks how a car's internal combustion engine works, do you tell them that water goes in the front of the car and gas in the back and both go in the engine? While true, it gives the impression that water and gas mix in the engine, which is false.

"Codominant" in the link gets over the concept that two genes, A and a, produce three gene pairs, AA, Aa, and aa. Genotype AA produces phenotype 1, genotype Aa produces phenotype 2, and genotype aa produces phenotype 3. What else does a breeder need to know about codominance?

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People aren't asking how it works, they just want to know how to pump gas. If they want to know beyond that, they aren't going to be reading material that starts off like this.

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This explanation is not meant to be taken as a scientific study or anything like that. It is written from a layman's point of view in order to offer a basic understanding of how genetics work in Ball Python breeding and the various genetic terms as they are commonly used in the BP community. Hopefully the visuals created for this lesson will provide a solid foundation for future learning.

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What is described in the link is what is generally accepted as incomplete dominance.

I've taken quite a few university genetics courses and have done some lab work as well. I personally find Judy's guide fine.
It's not suppose to be a text book. It's suppose to be guide. A cliffnotes of sorts.
While it doesn't go into depth, it does introduce the basic concepts of what is going on in Ball Python morphs and breeding. And for people who have never taken a formal genetics class, that's really all they need.

If you're not satisfied with any of the guides provided, then I encourage you to write one yourself. If it's good enough, perhaps it could be stickied.
:)

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Originally Posted by OhhWatALoser

What is described in the link is what is generally accepted as incomplete dominance.

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^^ This is true.

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Originally Posted by paulh

I looked at that site and abandoned it at the end of the third paragraph in the Genetics 101 file. There were so many mistakes that it wasn't worth going on further. The guy obviously put a lot of work in it, but I don't think he spent much time reading a genetics text. Too bad. :(

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Everyone is entitled to their opinion. So here's mine. If all you can do is bash other peoples work and have none of your own then shut up about it. Until you publish something involving the current topic then you don't have a leg to stand on imo. Just because you think you have a better understanding of genetics doesn't make you the authority. This thread was started with a simple question. Some of us tried to steer them in a direction to learn more and all you have done is tear down other peoples work. Do something productive lead them in the right direction with out being a butt about it. I like the vms page on genetics. I also liked the one on here. They make it simple to follow and give enough that the layperson can keep up with. It don't take a genius to understand a punnet square or how to get a super pastel or how a simple recessive gene works. That's pretty much all the average ball python keeper really what's to know. If you want an in-depth genetics discussion then you might want to find a forum that specializes in just that and not a forum dedicated to the love and enjoyment of keeping reptiles.

I like to check out the genetic wizard on World of Ball Pythons. It is very helpful. I also use John Barry's book a lot as well. Hope this helps.

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Originally Posted by OhhWatALoser

What is described in the link is what is generally accepted as incomplete dominance.

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The breeding results for codominance and incomplete dominance are the same. Explaining the difference would violate the keep it simple philosophy advocated in this thread.

For what its worth, I have contributed to the Lesson in Basic Genetics sticky. As they are closer to the end than the front, I don't think many people have looked at them.

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Originally Posted by H.o.F.R

This thread was started with a simple question. Some of us tried to steer them in a direction to learn more and all you have done is tear down other peoples work. Do something productive lead them in the right direction with out being a butt about it.

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http://www.redtailboas.com/f115/no-f...s-guide-53782/

I like a lot of things about the World of Ball Pythons, too.

*Facepalm*

A) There's nothing wrong with saying "That paper contains incorrect information". It's not rude.
B) Yes, if you're going to continue to complain about it, you SHOULD write your own, and submit it, as obviously you care.
C) If someone says you have incorrect information in your paper, and they are right, you should pull it and correct it, not complain because you put so much work into. Nor should anyone else complain on your behalf.

The point is, the information should be correct, and that is all. My 2 cents.

All the rest is weird social politics that I've never understood, and does not do breeders or the animals any good.

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Originally Posted by paulh

The breeding results for codominance and incomplete dominance are the same. Explaining the difference would violate the keep it simple philosophy advocated in this thread.

For what its worth, I have contributed to the Lesson in Basic Genetics sticky. As they are closer to the end than the front, I don't think many people have looked at them.

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Calling it co-dominant violates the make it 100% factually and visually correct philosophy.

So far your issue is with the picture, it doesn't even mention the word chromosome, it is on that basic of a level. You respond with a link that starts off with codons and proteins. Which do you honestly think has a better chance of teaching someone, who knows nothing, about inheritance?

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Originally Posted by OhhWatALoser

Calling it co-dominant violates the make it 100% factually and visually correct philosophy.

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100% correctness is impossible in this area because the textbooks do not agree on the definitions of "codominance" and "incomplete dominance". As the breeding results are the same for both, the simplest practical solution for breeders is to lump them together. "Codominant" has the fewest letters of the greater than a dozen possible available terms. This is the solution that the professional mouse geneticists have adopted, but they use the term "semidominant".

I've never seen different definitions, incomplete dominant = blending of phenotypes. Codominant = showing both phenotypes. What else says different?

Knight, Jeffrey A. and Robert McClenaghan. Encyclopedia of Genetics. Salem Press, Pasadena, California, USA, 1999. 2 vols.
Zubay, Geoffrey. 1987. Genetics. The Benjamin/Cummings Publishing Co., Menlo Park, CA. 1987, 973 pp. ISBN 0-8053-09100-3

Incomplete dominance occurs when one allele produces a functional product and the other does not. The result is doseage dependent. Two white genes produces white flowers, two red genes produces red flowers, a red gene paired with a white gene produces pink flowers. The functional product is produced only by the red gene.
Codominance occurs when both alleles produce a functional product. As in the A and B blood types. The heterozygous phenotype comes from each gene doing its thing and producing a mixture.
This gives a biochemical basis to separate red, white, and pink flowers from siamese, burmese and tonkinese cats. Pink flowers and tonkinese cats are intermediate between the respective homozygous types. But in tonkinese cats, both genes produce functional products. Robinson's Genetics of the Cat has some material on those cat genes.

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Originally Posted by paulh

Incomplete dominance occurs when one allele produces a functional product and the other does not. The result is doseage dependent. Two white genes produces white flowers, two red genes produces red flowers, a red gene paired with a white gene produces pink flowers. The functional product is produced only by the red gene.

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how do they come to the conclusion that the phenotype is only because of the red?

Under a microscope, white is the absence of red color.

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Originally Posted by paulh

Under a microscope, white is the absence of red color.

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But it isn't red or white, it is pink. I don't see how they can say the white isn't doing anything. I could see saying that with a dominant case, the "normal" gene doesn't have an effect if the dominant trait is present and even if there is two the phenotype is the same which is kinda what proves the normal is not having an effect. I don't see how they can define it that way in the white red pink case. Seems to me like the white and red are blending.... you know like the more common definition :)

I heard somewhere that the heterozygous flower's pigment granules are red under the microscope. Either the pigment granules are fewer in number or smaller or there is some other explanation for the pink color. But all my sources accept the nonfunction of the white gene as common knowledge.

I don't understand the statement about the normal gene not having an effect. The normal gene is for red, and it definitely has an effect. It's just that two red genes have a greater effect than one red gene has.

I think of codominance as being like a black coffee and white milk producing a brown colored mix. Both contribute to the final product's color. Incomplete dominance is more like black coffee and water. They also produce a brown colored mix. But only the coffee contributes color. The water just dilutes that color. If the white flower color gene produced a product, then the pink color would be the result of codominance, not incomplete dominance.

Does a breeder really care whether a blended phenotype in a heterozygous snake comes from two different genes with functional products or from two different genes, only one of which has a functional product?