I thought of a question when looking at my guppy fry today. To introduce you to guppy genetics, here are the three genes I'm referring to.
Here is an albino guppy. It has red eyes and no melanin in its scales: http://i00.i.aliimg.com/photo/v0/101291396/Full_Platinum_Guppy_Fish.jpg
Here is a gray guppy. It has black eyes and does express melanin in its scales: http://img.photobucket.com/albums/v415/Okiimiru/073-Copy.jpg
Here is a blond/gold guppy. It has black eyes but no melanin in its scales: http://i810.photobucket.com/albums/zz25/Nymox/Guppies/blondeguppy.jpg
My goal was to breed a solid white guppy that had black eyes. The fish I started out with were an albino platinum (solid white) male guppy and a gold female. I crossed the albino male to the gold female and got the gray guppy that's in the picture. Then I crossed the resultant gray offspring to themselves. Using a punnet square and assuming that gold and gray are on the same locus and albino is on some second locus with non-albino, I should have gotten 25% albino, 19% gold, 56% gray guppy offspring. But instead I got vast majority gray offspring and some gold offspring. It was about 75%gray/25%gold although I didn't count and cant say for sure. I do know that I don't see a single albino fry.
Which brings up the question: Are gray, gold, and albino all on the same locus? Are they all alleles of the same gene? Because if so, that would explain why I got zero albino fry, if the gold is dominantly expressed over albino. But then how did the albino grandfather carry and pass along the gray? I'm very confused about why I didn't get even a single albino fry.
