OK, I was reading the other post about mosaics and sterility, and now I was hoping someone could clarify the mode of inheritance for mosaic for me.
People are saying that mosaics are dominant (or I have also seen it listed as codominant), but then I saw people posting that from a mosaic x classic gray cross, the babies could be standard gray.
Did I misread this or is this correct? Are all the babies from a mosaic x classic gray pairing ALWAYS mosaic, or can they also be standard?
Just trying to figure out for myself if it is dominant or codominant...not that I am planning on breeding but I am a genetics geek If mosaic was codominant, then methinks that all the babies from whatever pairing you do would have mosaic coloring, but if mosaic was simply autosomal dominant, than this could explain standard babies showing up from such a pairing. Thanks in advance for the info, breeders!
Co-dominance means that one gene isn't totally dominant, nor is it totally recessive. There is (I think) a 50/50 chance of getting either a mo or a normal. That's why you never see any mo hets - because it HAS to have the shown trait (phenotype) to have the gene, since standard doesn't cover it up.
Actually Marissa, you would have to have mosaic hets if I'm not mistaken...otherwise there would be no way that a mosaic could have a standard gray baby. By mosaic het I mean in the sense that the mosaic glider is heterozygous, not that it is a "carrier." Because any glider "carrying" the dominant mosaic allele would, in fact, be a mosaic...so it's not an allele that could be masked.
The mosaic gene has been determined to be a dominant gene, meaning that any glider that carries it is mosaic. Let's say that the mosaic allele is M. Anytime a glider is mosaic an M has to be present, so the mosaic glider could be MM or Mm.
In order for you to get standard gray babies (mm) from a mosaic cross, the mosaic glider would have to be heterozygous, or carrying an m. This way if a mosaic (Mm) was paired with a standard gray (mm), about 50% of your offspring would be mosaic, and 50% would be standard gray, like what Lynsie just described.
That is assuming they are autosomal...and it sounds like mosaic might be codominant...which would make it a little different than I typed it above. Blood typing is a codominant system...probably the most commonly used example.
(Correct me if I'm wrong on all this as I'm going on genetics and have not bred any of these cuties myself).
That would be right, but there's a bunch of different Punnet squares used for different types of genes. The Punnet square you're describing is for recessive and dominant genes only. I'm making a diagram right now to make it a bit easier. (since words can make it hard to describe some stuff.)
Wow LOL you just gave yourself a crazy homework assignment with all those Punnett squares...but yup, you have the codominant thing exactly right Guess that clears it up for both of us, and anyone else who is curious enough to read the thread...great diagram for those who are not genetics geeks, hehe.
Re: Random mosaic genetics question
#627417 09/03/0808:07 AM09/03/0808:07 AM