I'm confuzzled..

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Posted by Hurley on April 21, 2003 at 23:19:42:

In Reply to: I'm confuzzled.. posted by Taceas on April 21, 2003 at 22:22:07:

:Hopefully that charcoal male will turn out to be het amel. That'd be a huge bonus for you to be able to produce blizzards in the first gen.

:Am I thinking wrong in thinking that a blizzard is amel x anery B? I thought for me to produce a blizzard, I need one parent amel (or het amel) and one parent charcoal (or het charcoal). Which I would have by having a blizzard female and charcoal male, correct?

Yeah, a blizzard is a combo of the amel and charcoal mutations. Thing is, though, that both mutations are recessive...don't know how much you know about genetics, so I apologize if I'm oversimplifying here.

In each chromosome pair there are two complimentary copies of genetic code. Take the amelanism locus (location on the chromosome pair), for example. If both chromosomes are mutated at the amelanism locus, the ability to produce melanin is lost and the snake is 'amelanistic'. In order for this to happen, BOTH of the pair must be mutated...i.e. the animal is homozygous for this mutation.

For grins, let's represent this as 'aa'.

'a' for 'amelanism', lowercase to denote that it's a recessive trait.

You would then let 'A' represent the wild type normal appearance.

So, with this solitary mutation, there are 3 possible combinations:
AA - normal, not het for amel
Aa - normal, het for amel (the normal gene goes ahead and codes for melanin, even though the other gene is defective)
aa - amelanistic - both genes 'defective' and melanin not produced

(btw, het = heterozygous = the carrier form in the case of recessives = the alleles (paired chromosomes) are different...Aa; homozygous = alleles are alike, the same...like aa or AA)

Same goes for charcoal. Let's just call it 'c'. A 'cc' snake exhibits the charcoal mutation because it has lost the ability on both genes to code for the erythrins. A CC snake is normal, non-het, a Cc snake is normal het charcoal.

In combo, a blizzard is 'aacc'. A charcoal is 'Aacc' or 'AAcc' .....

When producing an egg or sperm, the parent gives only one set of genetic code....only one version of 'a', one version of 'c', and so on.

So, your blizzard, being aacc can only give of 'ac' gametes.
The charcoal, if it's not het amel, is represented as AAcc and can only give off 'Ac' gametes.
(Whereas a normal het amel and char AaCc can give off 4 different gametes --> AC, Ac, aC, and ac.)

So, knowing this, breeding the charcoal to the blizzard:

Ac x ac = Aacc (Charcoals het for amel) 100%

If the charcoal is het for amel, then he's Aacc and can give off Ac and ac gametes in his sperm. The cross would then be Aacc x aacc:

Ac x ac = Aacc (50% charcoals het amel)
aa x ac = aacc (50% blizzards)

You'd get half blizzards and half charcoals het amel.

Does that make sense?

That's why breeding an amel (aaCC) to a charcoal (AAcc) gives you a clutch full of normals (AaCc) that are het for amel and charcoal.

My best recommendation is to read Serpwidgets' genetics tutorial. It's excellent and really hammers home what you need to know to work these genetics problems through.

Serp, what's that link addy again?

Hurley

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