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Devious_bunny
03-27-2005, 11:53 PM
Yay! you oh-so-helpfull, incredibly nice, people get to answer more of my rookie questions!

ok, heres the thing, I am a super wiz when it come to fish genetics...I did some breeding with Betta a while back, and I'm amazing at it! Unfortunatley... I'm having a real hard time understanding the gecko genetics. Especially albino. i just want to be sure before I rish out and buy a genitic mis-match for my female!

1) what do i get if i cross two different strains of albino? or one Het for one kind of albino, and one albino of another strain?

2) Het for albino + Albino = 75% chance of albino offspring? right??

3) het + het = 25% chance of albino, 50% chance of het, and 25% chance of no albino???

4) whats "double het"

Thank you! i can assure you i'll come up with more in the next few days :hehe: :D

aliceinwl
03-28-2005, 01:16 AM
1) what do i get if i cross two different strains of albino? or one Het for one kind of albino, and one albino of another strain?
You get double hets. This means that the offspring will apear normal but will be het (heterozygous) for two different strains of albino.

2) Het for albino + Albino = 75% chance of albino offspring? right??
If you have a het albino, and cross it with an albino of the same strain, you will get 50% albinos. A gecko will get one copy of every gene from each parent. The albino will have two copies of the albino gene so that's all it can pass on. The het has one copy of the albino gene so it can pass of either an albino gene or a normal gene. The offspring has a 50% chance of getting an albino gene from the het parent and being an albino.

3) het + het = 25% chance of albino, 50% chance of het, and 25% chance of no albino???
Correct

4) whats "double het"
Double het means that the gecko is het for two different recessive traits. For example if you cross an albino with a patternless you will get a normal appearing gecko that is carrying the recessive genes for both patternless and albino; a double het. The same would apply if you crossed two differnent albino strains, or an albino and a blizzard.

Hope this helps,
Alice

Devious_bunny
03-28-2005, 10:22 AM
:) Yes, it helps a lot

BluGnat
03-28-2005, 11:31 AM
For a gecko to be phenotypically albino, is that double-recessive??

aliceinwl
03-28-2005, 10:55 PM
When you say double recessive the implication is that the animal exhibits two different recessive traits, for example a patternless albino.

An animal that exhibits a single recessive trait such as albino, would be referred to as homozygous recessive. In the term homozygous, homo means same. It means that the animal has two identical copies of a gene. In this case it has, it has two recessive genes for a particular strain of albinism. This contrasts with the term herterozygous, where hetero means different; this term is shortened to het and refers to the state where the animal has two different copies of a gene. In the case of a het albino, it would have one copy of the dominant normal gene and one copy of the recessive albino gene.

When someone describes a double recessive, it is usually taken to mean the same thing as a double homozygous recessive meaning that it has two identical copies of two different recessive genes...

I hope this helps some,
Alice

BluGnat
03-28-2005, 11:28 PM
Oooh, I meant double recessive as in humans and blue eyes, and horses and the chestnut color - bb and cc (general example: two blue-eyed parents can only produce a blue-eyed child; two chestnut horses can only produce a chestnut foal)- but I see (still) that the Leo genetics are a LOT more complicated than that...but am learning! Thank you!