Reptile Forums UK  

Go Back   Reptile Forums UK > Help and Chat > Genetics

Reply
 
Thread Tools Display Modes
  #1 (permalink)  
Old 17-01-2008, 04:42 PM
Superbuzz3's Avatar
Forum Citizen
 
Join Date: Dec 2007
Location: Sunbury on Thames
Posts: 366
Default Hets

What is the deal with "Hets".

I understand that it means they carry a certain gene, but I dont get the percentage thingy.

What does a 100% HET Albino mean?

Also if you breed 100 % Hets to normals, do you get visuals, or just more hets? Do hets have to bred with hets to produce visuals.

Now Im starting to confuse myself!
__________________
4.1 Royal Pythons (Ghana, Oscar, Roxy, Marbles, Ginger)
0.0.2 Bearded Dragons (Lady & ?)
0.1 Girlfriend (Hayley)

R.I.P - Sahara - you wasnt with me long, but I miss you
Reply With Quote
  #2 (permalink)  
Old 17-01-2008, 05:20 PM
Ssthisto's Avatar
Try Ms Lovett's Meat Pies
 
Join Date: Aug 2006
Location: Huddersfield, West Yorks
Posts: 7,684
Blog Entries: 2
Send a message via Skype™ to Ssthisto
Default

100% het Albino means that there is a 100% chance that THAT animal carries the Albino gene.

(The only way to get one of these is to have one animal have an albino parent.)

If you breed a 100% het to a normal, you get 50% hets - there's a 50% chance that they'll pass a copy of the Albino gene to the offspring (and make a het) and a 50% chance they'll pass their NORMAL copy of that gene to the offspring (and make a not het). You can't generally tell which animals are hets - so they're all sold as possible carriers.

Same goes for a 66% het - there's a two in three chance they carry the gene, but a one in three chance they do not. (You get these by breeding two 100% hets.)

In order to get animals who visually display a recessive gene like Albino you have to breed carriers of the gene together - whether it be visual to visual, visual to het or het to het. If you get a visual out of a het to a normal crossing, you actually had two hets and just didn't know it.
__________________
- Ssthisto






We HAD a three-bedroom house... Current lodgers: 1.0 E. c. maurus, 0.1 P. regius
Reply With Quote
  #3 (permalink)  
Old 17-01-2008, 05:22 PM
Superbuzz3's Avatar
Forum Citizen
 
Join Date: Dec 2007
Location: Sunbury on Thames
Posts: 366
Default

Cool....thanks.

Easier to understand now
__________________
4.1 Royal Pythons (Ghana, Oscar, Roxy, Marbles, Ginger)
0.0.2 Bearded Dragons (Lady & ?)
0.1 Girlfriend (Hayley)

R.I.P - Sahara - you wasnt with me long, but I miss you
Reply With Quote
  #4 (permalink)  
Old 18-01-2008, 01:04 AM
Forum Citizen
 
Join Date: Sep 2007
Location: USA
Posts: 356
Default

Quote:
Originally Posted by Superbuzz3 View Post
What is the deal with "Hets".

I understand that it means they carry a certain gene, but I dont get the percentage thingy.

What does a 100% HET Albino mean?

Also if you breed 100 % Hets to normals, do you get visuals, or just more hets? Do hets have to bred with hets to produce visuals.

Now Im starting to confuse myself!
100% (probability) het is het plus a lot of unnecessary letters and numbers.

The probability was well covered, so I'll just go into detail as to what a "het" is.

A pair of genes is heterozygous (slang - het) if the two genes are different. By extension, a cell with a heterozygous gene pair is also heterozygous. And a creature with heterozygous cells is heterozygous.

Please note that there is no specification for what a creature with a heterozygous gene pair looks like. A creature with a normal gene paired with a mutant gene may look normal because the effect of the normal gene hides the effect of the mutant gene. If so, then the mutant gene is recessive to the normal gene. Albino in the royal python, corn snake, or leopard gecko is an example of a recessive mutant gene. Or the creature may not look normal. If so, then the mutant gene is dominant to the normal gene. Dominant white in cats (white fur and blue/yellow/green eyes) is an example of a dominant mutant gene. Dominant mutant genes can be subdivided into codominant mutants and (fully) dominant mutants, but it is not necessary to go that far here.

A heterozygous creature puts one member of the heterozygous gene pair into half of its sperm (or eggs) and and the other member of the gene pair in the other half of the sperm (or eggs).

A creature with two identical copies of a given gene in a gene pair puts one copy of the gene into all the sperm (or eggs). Since the two genes are the same, it does not matter which member of the pair is in a given sperm (or egg).

When a creature with a heterozygous gene pair is mated to a creature with two normal genes in its corresponding gene pair, all of the babies get a normal gene from the normal parent. Half the babies get a normal gene from the heterozygous parent and wind up with two normal genes. The other half of the babies get a mutant gene from the heterozygous parent and wind up with a mutant gene and a normal gene, making them heterozygous.

If the mutant gene is recessive to the normal gene, then the heterozygous creature looks normal, just like a creature with two copies of the normal gene in its gene pair. None of the babies show the mutant effect, and the mutant gene is carried along unseen. This is by far the most common state and is usually what herpers mean when they are talking about hets.

If the mutant gene is dominant to the normal gene, then the heterozygous creature does not look normal. In a het x normal mating, you can tell the heterozygous babies from the normal babies. The hets are visuals.

Mutant genes generally make the owner less likely to survive than the normal genes do. And dominant mutant genes tend to get killed off quicker than recessive mutants do because the dominant mutants are at a disadvantage when heterozygous. Recessive mutants usually get killed off when there are two mutant genes in the gene pair but survive when heterozygous. Which means that fewer creatures with dominant mutant genes survive and reproduce than creatures with recessive mutants. However, "fewer" is not the same as "none at all", and dominant mutants do occur sometimes.
Reply With Quote
  #5 (permalink)  
Old 18-01-2008, 01:08 AM
Premier Citizen
 
Join Date: Apr 2005
Posts: 2,313
Default

This should be made as a sticky - It gets asked all the time
__________________


MASSIVE Discounts on Exo Terra Terrariums

25% Off Exo Terra Repti Glo UV Tubes

50% off Reptile Caves!
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off
Forum Jump


Exotic Pet Sites


Help For Heros

All times are GMT +1. The time now is 09:06 PM.


Powered by vBulletin® Version 3.7.2
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.2.0
Copyright © 2005 - 2008, Reptile Forums UK (RFUK™)