Reptile & Amphibian Forums

what happens if i breed a pair of 100% hets? do i get the visual morph?
thanks!

from breeding two hets you have a 1 in 4 chance of the morph they are het for being produced.
-----
You all talk Balls,I talk Royals ;0)
www.alpharoyals.co.uk

thanks!
would the rest of the clutch be 100% het like the parents?
how would you maximize your visual morph chances then? do you breed the visual (assuming you get one) with a 100% het?

It should clear up a few thigns for you.
Joe Pociask Pythons - Genetics

You would get 25% Normals, 50% Hets and 25% Visuals

which really breaks down to:
25% Visuals
75% Possible Hets (66% possible) because you won't be able to tell the hets apart from the normals.
-----
1.1 Caramel Albinos
1.0 Spider
1.0 Mojave
1.0 Pinstripe
1.1 Piebalds
1.1 Het Caramel Albinos
0.3 Pastels
0.18 Normal Balls
1.0 Coastal Carpet Python
1.0 75% Diamond 25% Jungle Carpet Python
1.1 Red Albino Blood Pythons

The previous posters make the common mistake we see here every day. Its a simple misapplication of genetic probabilities.

Breeding a het to a het does not give you a 1 out of 4 visuals, or even 25% visuals and 75% possible hets, as the other posted suggested.

What genetics does tell us is this: In a simple recessive trait, a breeding involving a het to a het will give each INDIVIDUAL OFFSPRING a 25% chance of inheriting the hozygous (visual) condition.

Here's the difference in the two points of view. Lets say you subscribe to the 1 outa 4 thought process. In that case, lets say you have an 4 egg clutch. The first 3 pip and all appear normal. You might think then you have a high probability of the 4th egg being the visual, when in actuality you still have the same 25% chance. Its just like flipping a coin. If you flip heads the first 9 times, you still have a 50-50 shot of flipping heads on the 10th.

You could have an 8 egg clutch with all visuals or all possible hets, and any combination thereof. Even assuming very large sample sizes will not necessarily get you your 25-75 ration.

Just remember the percentages you read are PER EGG, not to be extended to ____ out of ____ for the clutch....

.

this does get very confusing...i've looked at the genetics square and just can't quite grasp it...i guess i need to find someone to sit down with me and really explain it...lol. The downside to being someone who learns better from doing than reading...

ok...obviously hets are less expensive because of the time it takes to get your visuals...assuming that you start with a pair of 100% hets...how do you get to producing more visuals then?

If you start off with a pair of hets and you breed them about 1 out of 4 of their babies will be the visual morph. Then if you take the Visual morph and breed it back to its mother or father you will get 50% hets and 50% morphs. Then if you breed two of the visuals together you will get 100% of the visual morph. So if you want the most visuals you will want to breed two visuals to produce all of the same visual morph.

thanks...does it matter whether the visual morph is male or female?

If you were going to buy only one visual, and one het, I would get the visual male. You can put the visual male with any female you own and the babies are going to be hets (100% chance). But to answer you questions, in any one breeding there is no difference whether your talking het male to visual female or het female to visual male...in either case, each individual egg would have a 50% chance of being a visual...

I actually said you have a 1 in 4 chance of getting your morph not 1 out of 4 will be visual!
-----
You all talk Balls,I talk Royals ;0)
www.alpharoyals.co.uk

Doesn't this contradict everything that the punntet squares prove? Doesn't the punnet square say that 25% of the babies will be the visual, not each baby will have a 25% to be the visual. I guess i'm just a little confused then. It was my understanding that 25% would be visual, 50% would be het, and 25% would be regular therefore making the babies 2/3 or around 67% het for the gene because you cant possibly know which animals would actually carry the genes because most hets and normals look a like.

the square works out everytime when you have a large sample of something. Breed 2000 het's together and I'm sure it will come out to the 25/50/25 percentages. But when dealing with the very small numbers of ball python eggs the odds don't always work out for ya. Just remember, if you get killed on the odds now you will make up for it in the future and if you kill the odds you will get burnt later, lol.
-----
Josh & Krysty Hutto
J&K Reptiles

Various Ball Pythons:::

1.0 striped vanilla
1.0 spider
1.2 Citrus Ghost and hets
1.2 Albino and hets
2.3 het Pied
0.6 50% poss het pied
1.1 Pastel (male has additional gene going on with him)
a bunch of normal female breeders
a bunch of normal female holdbacks and several rescued normal males

0.1 columbian boa, she's a feeding monster, controls my
over production of rats, lol
0.1 brazilian rainbow boa, another rat eating monster
1.1 corns

a BAD dog is MADE not bred, support the American Pit Bull Terrier as the greatest breed of dogs on Earth!!!!!

the punnet square (for het to het) shows "the odds" of what you can get only if you have 4 eggs so if you have 3 you have less chance or 5 or more you have more chance of getting one. But you still only have a 25% chance on each egg.
-----
You all talk Balls,I talk Royals ;0)
www.alpharoyals.co.uk

Ok so the punnet square shows the odds, and i completly understand that you could get all normal looking balls in a clutch from het to het breeding, but where is the 25% chance coming from for each egg to have the visual?

25% of the punnet square has the "letters" for the required visual reccesive morph.
-----
You all talk Balls,I talk Royals ;0)
www.alpharoyals.co.uk

Just treat the punnet square as if you threw all the genes from each parent into an egg, mixed them up and pulled out a pair then you have a 25% chance of pulling out the pair of genes required for whatever morph they are het for.
-----
You all talk Balls,I talk Royals ;0)
www.alpharoyals.co.uk

Its amazing to me how many herpers missapply genetic probabilities. I sent you an e-mail Jimmy, but for the rest of you, just a bit of clarification. If you want to do some further reading, pick up a higher level biology book or college genetics text, or research "law of idependent assortment" on-line.

Punnett squares do apply to EACH INDIVIDUAL offspring, not clucthes.

Lets look at albinism in BPs. In a het to het breeding, druing meiosis (the type of cell divsion that creates sex cells) mom can donate either the dominant or recessive allele, completely at random (there is a .50 chance of getting a copy of the recessive allele into a given egg). Dad can also contribute either the dominant or recessive allele (again, .50 chance per sperm cell). Therefore the probability that any one ofspring would be homozygous recessive is .50 X.50, or .25 (25%).

Contrary to popular belief, the odds don't "owe you". IN other words, if you have crappy odds one season, it does not mean you can expect better odds next year. Lets say you have a monster 16 egg clutch (we wish, right). Anyway, lets say all of these babies look normal...you completely missed. The next year, each offspring still has the same 25% chance of being an albino. remember, each egg is an individual event. Think coins. Flip a quarter 20 times, and its possible that you see ole' George all 20 times. On the 21st flip, its still a 50% chance of being heads. You can not, nor should not, expect the tails to "catch up".

The same goes with possible hets. Some folks think you increase you chance of actually getting a het if you buy all the offspring from the same clutch. In actuality, you could buy all of the offspring each from a different clutch and have exactly the same odds.

Actually I mispoke, the law of indepentant assortment deals with dihybrid crosses (two traits). As it appplies to BPs, the law of independant assortment explains why you can breed double hets together and get the outcomes you see. In the case of bredding two double het for both snow traits, you can get albinos, axanthics, snows and normal appearing hets>

Medals law that applies to the random process involved in gamete production is commonly known as the law of segregation.

Sorry...

know what your saying but also if you have 10 eggs het X het you have around a 94% chance of producing said morph even though each egg is like you said 25% chance of morph.
http://snakemorphs.home.comcast.net/odds.htm#table
-----
Vince Pramuk

Absolutely. What that formula does is take the individual ODDS as figured by the punnett square, and then give you a PROBABILITY of getting your morph in various cases.

Great page for the stat people....

One nerdier step further:

For genetic probabilities of 50% on a single egg (e.g. homozygous to heterozygous)

The probability of getting exactly X of the mutation in N eggs is:

N!
-----------------
2^N * X! * (N-X)!

For genetic probabilities of 25% on a single egg (e.g. heterozygous to heterozygous)

The probability of getting exactly X of the mutation in N eggs is:

N!
----------------- * 1/(summation for i=0 to N of A)
2^N * X! * (N-X)!

N!
Where A = ------------
i! * (N-i)!

Or more simply it's the number of possible combinations of the number or morphs you want divided by the total number of possible combinations....

I'll work up a spreadsheet that gives this info and post it on our site.....interesting stuff......

that didn't format right....

also the second formula is wrong....too long since I took my advanced stat class

;0)
-----
You all talk Balls,I talk Royals ;0)
www.alpharoyals.co.uk

thanks so much for your help...i think it's starting to make sense! you guys are the greatest about sharing your knowledge and time! thanks again!

Here is a pretty good link that has tables that show you statistical chances of producing a visual from het x het. As you can see it is not as simple as just saying 1 in 4 will be a visual. A four egg clutch only gives you about a 68% shot of hitting the visual.
snakemorphs.home.comcast.net/odds.htm#table
-----
John Vandegrift

You and Vince hit on the same link. I need to go over there and check it out. The point being, most folks look at the punnet square and feel like a 4 egg clutch means you'll almost certainly get 1 visual...when in fact, theres a 32% chance you wont...

>what happens if i breed a pair of 100% hets? do i get the visual morph?

Hets have a gene pair in which the two genes are different. Generally these are a normal gene and a mutant gene. The mutant gene can be dominant, codominant, or recessive to the normal gene. When breeding two hets, each egg has a 25% chance of holding a baby with two normal genes in the gene pair, a 50% chance of holding a baby with a normal gene paired with a mutant gene (a het), and a 25% chance of holding a baby with two of the mutant genes in the gene pair.

Hets for a recessive mutant gene look normal. When breeding hets with a normal gene and a recessive mutant gene, the probabilities are as follows:
25% normal//normal (looks normal)
50% normal//mutant (looks normal)
25% mutant//mutant (shows the full mutant effect)

Hets for a dominant mutant gene look like animals with two copies of the mutant gene. When breeding hets with a normal gene and a dominant mutant gene, the probabilities are as follows:
25% normal//normal (looks and is normal)
50% normal//mutant (shows the full mutant effect)
25% mutant//mutant (shows the full mutant effect)

Hets for a codominant mutant gene do not look normal and do not look like animals with two copies of the mutant gene. (Pastel is a codominant mutant gene in ball pythons.) When breeding hets with a normal gene and a codominant mutant gene, the probabilities are as follows:
25% normal//normal (looks and is normal)
50% normal//mutant (looks like the het parents)
25% mutant//mutant (shows the full mutant effect)

The others have discussed breeding two hets for a recessive mutant gene. You should have the results when dominant and codominant mutants are in play, too.

Paul Hollander