Punnett Square

I'm trying to be a lady and not lower myself to his level...

Quote:

---

Originally Posted by All Balled Up

I have a question in regards to doing punnett squares. I know the basics of how to set them up with single gene animals. I can also set them up when both animals are double gened. I am just curious how you would set up a square for breeding a single gene morp to a double gene morph. Do you have to add extra filler letters to the single gene? Just something I would find convenient to know instead of using the calculators online.

Brennan

---

One of the things the books do not tell people is that a vertebrate has many thousands of gene pairs. But that is too many to deal with at one time. So, FOR SIMPLICITY, the convention is to ignore every gene pair that either is or can be assumed to be normal in both parents. When one or both parents has a pair of normal genes corresponding to the other parent's mutant gene pair, you fill in the normal gene pair.

All genes are either mutant genes or normal genes.

A normal gene is the most common gene in a given gene pair in the wild population.

A mutant gene is NOT the most common gene in a given gene pair in the wild population.

Example: albino male (aa) x Pastel female (Pp)
A = normal
a = albino

P = Pastel
p = normal

Fill in the previously ignored but now required normal gene pairs:
albino (aa pp) x Pastel (AA Pp)
All other gene pairs either are or can be assumed to be two normal genes. These are ignored.

The sire gives one member of each gene pair to each sperm, and the mother gives one member of each gene pair to each egg.

All of the albino's sperm are a p.
Half of the Pastel's eggs are A P and half are A p.
From here, running the Punnett square is easy.

Hope that helps.

Pretty much what I said, except better representation of albino being recessive which I didn't do properly. Other than that..

Sent from my DROID2 GLOBAL using Tapatalk

That is a great representation. Definitely makes more sense to me now. I find genes to be very intriguing. Makes me think I should have gotten my degree in biology instead of accounting. haha