# Offspring with the parents



## Mac (Aug 14, 2007)

I was wondering what your thoughts were on putting offspring in with the parents. They most likely will breed in the future, is that frowned upon, or what is best to do in this situation. Of course there is always sell it.

Just wanted to see what you guys thought.


----------



## sports_doc (Nov 15, 2004)

Mac, unless your intent is some type of experimental line/trait breeding, then I'd say the best thing to do is to trade someone for like frogs with different parents. 

S



Mac said:


> I was wondering what your thoughts were on putting offspring in with the parents. They most likely will breed in the future, is that frowned upon, or what is best to do in this situation. Of course there is always sell it.
> 
> Just wanted to see what you guys thought.


----------



## tkromer (Dec 20, 2007)

Linebreeding is pretty well understood and easy enough to do if that's what you're going for, but unless you are really trying to achieve some specific trait I would avoid linebreeding. You can likely find someone who will trade you 1 to 1 for the same frogs from different parents, even if you may have to eat the cost of shipping. Better gene diversity is almost always a good thing, but linebreeding can work as well, I just wouldn't recommend it unless you're trying for something.


----------



## Mac (Aug 14, 2007)

So what you are saying is go for different frogs from different parents, but have the same lineage? 



tkromer said:


> Linebreeding is pretty well understood and easy enough to do if that's what you're going for, but unless you are really trying to achieve some specific trait I would avoid linebreeding.


But I thought that you didnt want to mix lines, so that you dont muddy the line? Am I confused?


----------



## cindre2000 (Dec 17, 2007)

You don't want to mix morphs. Usually, unless you have a very uncommon frog there should be multiple lineages of the same morph (lots of people breed Azureus for example). Leucs, Auratus, Tincs, etc usually fall in this category. Occasionally you get some interesting vents, pumilo, imitators, etc that are from very specific wild caught or farmed lines and you need to be sure to not mix those morphs with other morphs unless they are from the exact same area.


----------



## Nubster (Jun 16, 2008)

Does this also apply to sibling frogs since I would assume that many times when a group of frogs is bought at once from a single source this would be the case. For example next week I am ordering a group of 5 terribilis from a single source. While breeding is not a primary goal at this point but eventually I would like to see that occur. Should I also think about trading out some of my frogs at some point?


----------



## markbudde (Jan 4, 2008)

Animals are as similar to their siblings as they are to their parents, and people cross siblings all the time. As always, its better to not breed close relatives, but it most likely won't be to much of a problem.


----------



## cindre2000 (Dec 17, 2007)

Actually, when the gametes are formed in the parents, the cells are given half of the parents genetic information. However, this does not mean that every other gamete has the same genes. Before the gene is split you might have AaBBccDdEe, which can then become:

ABcDE and aBcde
or
ABcdE and aBcDe
or
ABcDe and aBcdE
or
ABcde and aBcDE

This is of course very simplified since genes are very much longer, with many more allels. However, you can see that there is a multitude of possibilities, not taking into account the mistakes that can take place that change the genetic material even more.

Now since each parent has '2' possible genetic lines Ff for the father and Mm for the mother, the offspring can then be FM, Fm, fM, or fm. Therefore the offspring have a wide range of unrelatedness that is mostly up to chance. This means *two offspring are only 25% related *in many cases. Unlike their relatedness to their parent, *which is always 50%*. Therefore, you are much more likely to hit genetic snags when breeding offspring to parents vs. siblings to each other.

HOWEVER, it is probably best to get some new genetic material when possible since you are probably less likely to uncover deleterious recessive genes.


----------



## cindre2000 (Dec 17, 2007)

On to deleterious recessive genes. Suppose the mother has a gene 'alpha' that has an allel on it that is called Dd. This allel is a deleterious gene that causes a higher rate of SLS; however, since it is a recessive trait, it only is rears it head in carriers that are dd. Thus the mother is not effected. Since this trait normally prevents a frog with the dd allel from producing many viable offspring; it is normally only continued through the genetic line as Dd. Further more, it is an uncommon allel since its carriers generally are less genetically fit, since two Dd carriers mating produce less offspring (since 25% usually have SLS). However, since the trait is not deleterious when carried as Dd, the allel still floats around in the population, and is difficult to fully remove.

----

So the mother reproduces with another frog: Dd x DD;
The offspring produced are: DD, DD, Dd, Dd; 50% are carriers of this deleterious gene.

If the offspring reproduce with each other:

DDxDD = DD
or
DDxDd = DD, Dd
or
DdxDd = DD, Dd, dd

In the end you have *58.3% DD*, *33.3% Dd*, and *8.3% dd*.

If you cross the mother with her offspring:

DdxDD = DD, Dd
or
DdxDd = DD, Dd, dd

In the end you have *37.5% DD*, *50% Dd*, *12.5% dd*.

Since you do not know the carrier of the gene you must include the father's crosses as well:

DDxDD = DD
or
DDxDd = DD, Dd

Averaging out to *56.2% DD*, *37.5% Dd*, *6.3% dd*


So, with sibling crosses you a little under a 42% to continue the trait, while in parent crosses you have a little under 44% chance to continue the trait. But then again, statistics and probabilities only work in large populations with multitudes of chances; if you place a carrier sibling with a carrier adult (a 25% chance) you have over 10% of your offspring being full carriers and another 50% passing the trait along. And while you may not every see the dd's in your breeding population (due to SLS), you are still artificially increasing the number of frogs actually carrying the trait (Dd).


----------



## markbudde (Jan 4, 2008)

cindre2000 said:


> This means two offspring are only 25% related in many cases. Unlike their relatedness to their parent, which is always 50%. Therefore, you are much more likely to hit genetic snags when breeding offspring to parents vs. siblings to each other.


This isn't true, on average. If the parents are completely unrelated each has two unique alleles, as in your example, the offspring can be anywhere from 0 to 100% similar, with an average of 50%. Offspring will always be 50% identical to each parent. So, offspring can be either closer to each other or to their parents, but on average it is the same.

For the second post with some math in it, I'm not sure how you got those numbers, but here is what I get:

Brief into for those not well versed in genetics. Each frog has two copies of each gene. Here, the good copy is “D” and the bad copy is “d”. A single copy of D is enough to make you healthy, but two copies of d, written as “dd” results in an undesirable frog, which is what we are trying to avoid.

The father has 2 good copies “DD” and the mother has 1 good and 1 bad “Dd”.

Mother (M) = Dd
Father (F) = DD

All of their offspring are either Dd or DD because the both get one copy of the gene from each parent. Here “0.5” means 50% and 1 means 100%. So each offspring has a 50% chance of carrying the bad gene.

girl offspring (g) = 0.5*Dd “g1” + 0.5*DD “b2”
boy offspring (b) = 0.5*Dd “b1”+ 0.5*DD “b2”

Where “1” of “2” indicates the offspring’s genotype
--------------------------------
For a cross of the offspring to the parent, we must work out the probability of each cross individually (M x b and F x g).

Mother to son
M x b1 = 0.25DD + 0.5Dd + 0.25dd
M x b2 = 0.5DD + 0.5Dd

Father to daughter
F x g1 = 0.5DD + 0.5Dd
F x g2 = 1DD

So in total, the parent x offspring cross gives:
56.25% DD, 37.5% Dd, and 6.25% dd (affected frogs)
----------------------------------
We must also work of the sibling crosses individually

b1 x g1 = 0.25DD + 0.5Dd + 0.25dd
b1 x g2 = 0.5DD + 0.5Dd
b2 x g1 = 0.5DD + 0.5Dd
b2 x g2 = 1DD

So in total od the sibling cross we get:
56.25% DD, 37.5% Dd, and 6.25% dd (affected frogs)

Thus, you are no worse off crossing a siblings verses crossing child to parent, the result will be the same.
-mark


----------



## Mac (Aug 14, 2007)

Wow, my head hurts :lol:


----------



## kristy55303 (Apr 27, 2008)

Mac said:


> Wow, my head hurts :lol:


lol mac...my favorite subject is genetics. i loved it, although it would probably give most a headache yes. Biology and anatomy/physiology are my favs in college along with the study of genetics.. :lol: kristy


----------



## Sarkany (Mar 11, 2008)

cindre2000 said:


> DDxDD = DD
> or
> DDxDd = DD, Dd
> 
> Averaging out to *56.2% DD*, *37.5% Dd*, *6.3% dd*[/color]


No. What you just bred there can never ever produce "pure" (I don't know what you guys call it, in German it's _reinerbig_) dd! So where exactly did you get the 6.3%?



markbudde said:


> For the second post with some math in it, I'm not sure how you got those numbers (...)


Going to add my two cents to the math thing. :wink: 
Sooo, cindre2000 assumed the mother to be the carrier of this ominous harmful recessive allel (carrier, but not afflicted, as in "Dd". In Germany we call this _Konduktor_, but I don't know the English word, sorry). She (?) also assumed the father not to be a carrier of said harmful allel.

D: dominant 
d: recessive

DD: non-carrier
Dd: non-afflicted carrier
dd: afflicted

So, the frogs you have are: female Dd, male DD
Therefore:

P (parental generation):	DD x Dd	

F1 (filial generation 1):
__D__d
D	DD	Dd
D	DD	Dd --> 1:1 (“non-carriers” and “carriers, but not afflicted”)


Now, when you breed two F1 siblings, you can get this:
F2:
a) DD x DD

__D__D
D	DD	DD
D	DD	DD --> in a), all F2 are pure non-carriers.

or b)	DD x Dd

__D__d
D	DD	Dd
D	DD	Dd --> 1:1 

or c) Dd x Dd

__D__d
D	DD	Dd
d	Dd	dd --> 1:2:1 (“non-carriers : “carriers not afflicted”: “afflicted”)


12 F2 on the whole, out of these seven are DD, four are Dd, and one is dd (actively sick).

Thus --> *DD: 58.33 %; Dd: 33.33 %; dd: 8.33 %*

OR you can breed the P female (Dd) with a F1 male:

a) Dd x DD

__D__d
D	DD	Dd
D	DD	Dd --> 1:1 considering genotype

b) Dd x Dd 

__D__d
D	DD	Dd
d Dd	dd --> 1:2:1

With eight F2, you have three DD, four Dd and one dd.
--> *DD: 37.5%; Dd: 50%; dd: 12.5%*

OR you can breed the P male (DD) with a F1 female:

a) DD x DD
--> all DD

b) DD x Dd
__D__d
D	DD	Dd
D	DD	Dd 1:1

Eight F2, six of them DD, two Dd:
*--> DD: 75%; Dd: 25%, no dd.*

So yeah, theoretically, if you picked a parent that was Dd and bred it with any F1, you’d be spreading the d of course. However, seeing as, when breeding two F1 siblings, the chance that you have a Dd in the pair is 50% (as seen above); and the chance to pick the “non-afflicted carrier” of the parental generation is 50% as well (when breeding P x F1), I’d say that’s a pretty even risk. 

All of this is of course nullified by the fact that the P generation are probably already siblings, which means you’ve got a good chance that both P individuals are “non-afflicted carriers”, in which case the whole point is moot. 
Because, of course, Dd can only appear in a F generation which had at least one Dd parent, or two:
DD x Dd or Dd x Dd
__D__d
D	DD	Dd
D	DD	Dd	--> 1:1

__D__d
D	DD	Dd
d	Dd	dd --> 1:2:1

A good chance that you’ve got two Dd to start with. Well, let’s not be pessimistic. (Our froggies' luck there is no such overtly harmful highly SLS-inducing allel... :roll
Well, now I’m feeling like I’m back in ninth grade with all this Mendel stuff going on... :lol: 



markbudde said:


> This isn't true, on average. If the parents are completely unrelated each has two unique alleles, as in your example, the offspring can be anywhere from 0 to 100% similar, with an average of 50%. Offspring will always be 50% identical to each parent. So, offspring can be either closer to each other or to their parents, but on average it is the same.
> -mark


I have to agree with you there. Since we’re all happily inbreeding our frogs anyway :roll: , does it really matter whether it’s two siblings or a parent and a sibling? They are all close relatives, after all. I think it's much more important over how many generations inbreeding occurs.


----------



## cindre2000 (Dec 17, 2007)

First of all. My point is offspring are, on average, *25%* related to each other. Offspring are 50% related to their mother and 50% related to their father, 50% x 50% = 25%. This of course can vary a good bit, but the variability within the allocation of genes in the gametes almost ensures that you get fairly close to this number.

I just went on about deleterious recessive genes as a tangent. But I think my numbers are right, that last one is with the addition of the father x offspring cross with the mother x offspring cross.


----------



## Sarkany (Mar 11, 2008)

cindre2000 said:


> I just went on about deleterious recessive genes as a tangent. But I think my numbers are right, that last one is with the addition of the father x offspring cross with the mother x offspring cross.


Be that as it may (and I'm sorry you're so easily offended, I didn't mean to offend in the first place), it still doesn't explain how a "DD" parent could *ever * produce a "dd" offspring. 
Pray tell, how exactly did you come to the conclusion of 6.3% dd when the father (DD in your example)
is used for breeding?
If you've read my first post you will have seen that I actually agree with you on the numbers concerning F1xF1 and P female x F1. 
However, you can not breed a DD and have dd offspring appear. _That is just not possible_. To get a dd frog, both parents will have to "contribute" a d.

Edit: Wait, my bad.  I should learn not to skim over things so fast. :roll: Since you apparently didn't only mean the father x F1 up there (it was the color that tricked me :lol: ), I take back what I just posted in my second post here.


----------



## cindre2000 (Dec 17, 2007)

I'm not offended. Its just that at least one poster said that offspring are as related to each other as their parent. That is not true; offspring are usually less related to each other than their parent. That is a very basic fact that makes breeding offspring to each other less deleterious than offspring to parent crosses.

As for the 6.3%; if you read very carefully; and if I could rewrite it to make it easier to understand  . What I was trying to point out; is that you do not know which parent carries the gene, thus you generally should assume the cross between the proverbial father _as well_. Thus, that was not just the cross father x offspring; that was both the father x offspring and mother x offspring cross. In actuality:

Dd x DD
Dd x Dd
DD x DD
DD x Dd


----------



## Sarkany (Mar 11, 2008)

That's good, that you're not offended I mean. Actually I just edited my last post post, because I had a sort of "duh! cindre even wrote that it wasn't the father only" moment (that was before I read your last post) - you're right, I do need to pay better attention when reading.


----------



## cindre2000 (Dec 17, 2007)

Yeah, that probably was confusing. The only time I got irritated was the idea that children are mostly 50% related; which they are not. Your numbers are more accurate anyways because I rounded a bit.


----------



## salix (Mar 28, 2008)

Sarkany said:


> However, you can not breed a DD and have dd offspring appear. _That is just not possible_. To get a dd frog, both parents will have to "contribute" a d.


I've always had a genetic/math geek interest in genetic charting. When my son was breeding rabbits, I loved to color chart the possibilities. And much like SLS, the dwarfing gene in rabbits is a fatal gene. All dwarf rabbits carry NORMAL/dwarf genes. The numbers will give you 25% NORMALS (unshowable and much larger pets), 50% dwarfs and 25% what are called peanuts which carry the double dwarf gene. These kits (baby rabbits) will always die within a few days. In fact, they somewhat resemble SLS :?: 

I find it interesting when seeing new human babies and noting the baby is carrying a dominant feature (such as eye or hair color) and the parents both carry a recessive :shock: :wink:


----------



## cindre2000 (Dec 17, 2007)

Heh, I did not know that about rabbits; however, my mini rex is about to be neutered so I think it is unlikely he will have offspring.


----------



## Rich Frye (Nov 25, 2007)

Sarkany and cindre2000,
As far as I know, I don't think there has been an "SLS gene" ever identified. In fact, most in the hobby contributes SLS to other factors. Not proven either way, but you may wish to use another trait as an example so as to not give the impression that SLS is factually a genetic factor.

Rich


----------



## Sarkany (Mar 11, 2008)

salix said:


> Sarkany said:
> 
> 
> > However, you can not breed a DD and have dd offspring appear. _That is just not possible_. To get a dd frog, both parents will have to "contribute" a d.
> ...


That is not a complete dominant recessive inheritance (if inheritance is the word I want here , I still get my English wrong sometimes, ah, bless you secondary language) it's an intermediate/ incomplete dominant one. :wink: 


Edit: Certainly, Rich.
Cindre2000, Mark and I were only speculating (with a little help from Mendel) what would happen were one to breed an animal that is "Dd" with the d being a harmful recessive allel. *The SLS mentioned was purely an example. We never meant to give off the impression that there is a known gene to induce SLS. *


----------



## markbudde (Jan 4, 2008)

Let me preface by saying that I am only trying to set the record staright here. This is a topic which comes up occasionally, and I want to make sure that if somebody searches then they can come across correct information. I am not trying to offend anyone.

I think my math was laid out clearly in my previous post, but of someone has a specific question with it feel free to comment. I stand by the the fact that siblings are, on average 50% genetically identical, and are exactly 50% genetically identical to each parent (for genes which are not identical in both parents). Crossing siblings is inbreeding to the same extent as crossing to parents.



Sarkany said:


> Now, when you breed two F1 siblings, you can get this:
> F2:
> a) DD x DD
> 
> ...


Sarkany, good start, you clearly know a lot about genetics. You made a minor mistake in that you omitted one cross. The middle cross in your example is twice as likely as the other two listed, because either sibling can have either genotype, so you must count it twice. So the total number of potential F2 offspring is 16, not 12. When you count in the extra cross you get the same ratio as in my example.

And when you average your parental crosses (because you would have no idea which parent carried the mutation) you get the same as I did as well. So whether you are crossing siblings or crossing back to parents, you get 56.25% DD, 37.5% Dd, and 6.25% dd. Identical risk in both cases.



cindre2000 said:


> My point is offspring are, on average, 25% related to each other. Offspring are 50% related to their mother and 50% related to their father, 50% x 50% = 25%. This of course can vary a good bit, but the variability within the allocation of genes in the gametes almost ensures that you get fairly close to this number.


Cindre, good start, you're halfway there. Siblings are on average 50% related, as follows:
Baby Girl gets 50% of her genes from mom. Baby Boy also gets 50% of his genes from mom. 
0.5*0.5=0.25, so Baby Girl and Baby Boy each share 25% of moms DNA, as you correctly pointed out (the other 25% of their DNA from mom they don't share with each other).

But we must also remember that Baby Girls gets the other 50% of her DNA from dad, as does Baby Boy. So Baby Girl and Baby Boy each share 25% of their father's DNA with each other (the other 25% that the get from dad is not shared with each other). Since they share 25% from mom, and 25% from dad, they share a total of 50% the same DNA. From this we can also see that they each have 50% DNA (25% from each parent) that they don't share with each other, and we can add up both to check our math and get 100%.

Sometimes I have trouble expressing myself clearly, so here is a link I found on google with a longer explanation.
-mark

p.s. sorry for all the math.


----------



## Mac (Aug 14, 2007)

well done people you have successfully and officially hijacked my thread :x :lol:

I will now treat my headache from all these numbers and endless disagreement.


----------



## Mac (Aug 14, 2007)

just so you know I am not at all mad I was just ribbin ya. No need to feel bad.  

Continue your discutuion , I dont mind at all.


----------



## salix (Mar 28, 2008)

cindre2000 said:


> Heh, I did not know that about rabbits; however, my mini rex is about to be neutered so I think it is unlikely he will have offspring.


You'd be okay here anyway :wink: . Mini Rex are not dwarf rabbits, just bred selectively for size. Now that is a breed with a huge range of colors, very fun to chart with the multiple colors, dilution factors, the patterns such as tan points. And then of course selectively bred for the rex coat type.


----------



## salix (Mar 28, 2008)

Ah Mac, I figured I was okay since you have a Dutch :wink: 

And I want to say, I also wan't implying a genetic link with SLS. It just struck me as odd when I was typing about "peanut" rabbits the similarity with how they look and the photos I've seen of froglets with SLS. Also, with the rabbits, it is a 100% fatal combination within days. From what I've read, the same is true with human dwarfs, if both parents supply a dwarf gene, the baby will not survive. I don't know if SLS is an automatically fatal condition so much as a condition which causes the frog to not thrive.


----------



## Mac (Aug 14, 2007)

You know I us to breed Dutchs, ( on a very small scale) and once we had the babies get laid on the wire, and rats came and ate the feet off!!, Pretty disgusting, they are pretty helpless when they are days old. We also had a runt, they seem to always have a big head, and a small body, this one had a huge forehead! :lol: 

It was a fun experience, especially when the babies learn to get out of the nest box, very hard to resist cuddling with them. If there is one thing I hated, was trying to find buyers for them, big pain in the ass.

Just thought i'd share :wink:


----------



## salix (Mar 28, 2008)

Mac said:


> If there is one thing I hated, was trying to find buyers for them,


I can put that in perspective for you. Not counting babies in the nest boxes, my son had 200+ rabbits in his herd. Try going through 50 pounds of rabbit feed per day (plus hay, supplements, etc)! :shock: I think they named a wing after us at the local feed store :roll:


----------

