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jjnnbns
04-23-04, 07:52 PM
How can something be 100% het for a trait? Wouldnt some babies be normals with other 66% hets?

If say, a normal female were bred to an albino male, could you know FOR SURE that the babies would be 100% het? Would this be possible without the female being het for albino?

I didn't think so, but that's what I was told by someone trying to sell me one.

Thanks,
Brent

Tim_Cranwill
04-23-04, 08:34 PM
This will explain it all to you... http://www3.mb.sympatico.ca/~cranwill/faq22.html

But...

There are no real % hets. Either animals ARE het or they aren't. The % comes in when in a clutch you get an albino and have the 3/4 normal looking snakes in that same clutch. The albino is obvious but odds are only 2/3 normals are hets and the other does not carry the recessive gene. So... all 3 normal are called 66% possible hets. They could all be het or none of them could be het. That number is based on the odds you can "expect" to get. :)

But read my sheet. I spent more time writing that than this response and it probably makes more sense. :D

gonesnakee
04-23-04, 11:35 PM
When an albino is bred to a regular all the babies will appear regular but they will all be hets (100%) for sure zero doubt. Mark

Icefire
04-29-04, 06:15 PM
Albinos X Regular will give you all Het for Albinos.
Het Albinos X Het Albinos: Possibility of 25% Albinos, 50% Het, 25% normal
in that case, 50 on 75 are possible het, 50/75 = 66% Possible Het
because you can't know without breeding it if it's het or not

M_surinamensis
04-29-04, 08:35 PM
Tim, EXCELLENT explaination of basic mendelian genetics, easy to read, easy to follow and accurate.

The only way for a monkey wrench to be thrown into the clear cut genetics of simple recessives is for a female to be bred to multiple males, either in the same season or previously... While it's not common, sperm retention is certainly possible and fertile offspring can be produced YEARS after actual copulation. Responsible and reliable breeders generally undertake projects ONLY with virgin females or using males with the same genetic breakdown (meaning they might switch males, but the males are genetically identical when it comes to the specific trait that the resulting offspring might potentially end up as).

The other important thing to remember is that an animal either is het or is not (as was mentioned) and that the percentages on possible hets represent the chances for each individual neonate. Using a punnet and determining that you have a twenty five percent chance for any given zygote to end up as (for example) an albino does not mean that one out of every four neonates produced is guaranteed to be such. Similarly when 66% possible hets are produced, there's no guarantee that two out of every three from any given drop will be hets, the chances are "reset" for each animal produced.

Tim, would you mind if I were to link others to your site when discussions on this forum or others ends up on this topic? It's truly the best website dealing with the topic as it relates to basic herp genetics and breeding that I have ever seen... I don't want to be responsible for exceeding any bandwidth limits or killing your server speed if it's an issue though.

klein
05-03-04, 07:19 PM
in your article you are talking about snakes, or at least that is what you breed. Would this same scenario work for leo's and/or beardies?

Jeff_Favelle
05-03-04, 09:17 PM
Genes are genes. Menelian genetics work in all living things the same way, including plants, protists, fungi, etc etc.

Tim_Cranwill
05-03-04, 10:08 PM
M_surinamensis, feel free to link to any of my articles... and that goes for anyone else as well. I wrote them for the benefit of anyone who wishes to use them. :)

If I get THAT much traffic, I'll upgrade my server! :D