Re: Is banana/coral glow sex linked?
Quote:
Originally Posted by
TessadasExotics
Simple actually. Birds, some insects, some reptiles and a few others use a ZW sex determining system in the ovum, which is in contrast to the XY and XO system which uses sperm.
This particular sex determining factor regarding Bananas/CG only pertains and is linked to the banana/cg phenotype which is why the normal offspring void of this genetic defect are not affected by it. It also only affects male Banana/cg which again shows that it is indeed a SEX linked gene.
There has been a few fish, some insects as well as some human diseases which act in a very similar if not exact way.
Even though the "normal" is XY, XO or ZW one can also have many combinations and many defects. So things like XXY, XXXy, XXYY, XXYYY, XaYa, etc.
Ok, I understand how normals wouldn't be affected, but I'm still confused on why female bananas wouldn't be affected if it is carried on a sex chromosome. Females and males have at least one Z, so wouldn't that mean they would both be affected? Also, you haven't answered the question of whether that would mean only males could be super bananas. Do you have examples of particular species that act in this manner? I think I'll understand your theory better after this is clarified.
Re: Is banana/coral glow sex linked?
Here is why I believe that banana is not a sex-linked (Z-linked) gene.
If the banana gene is located in a Z chromosome, it would work like this: A normal male has 2 normal Z chromosomes. It does not matter which Z chromosome the father gives a baby because both are normal. Banana female has a Z chromosome with a banana gene and a W chromosome. Mating these produces males with a normal Z chromosome (from father) paired with a Z chromosome with a banana gene (from mother) and females with a normal Z chromosome (from father) and a W chromosome (from the mother).
Father --- Z
mother
Z ------- ZZ (male)
W------- ZW (female)
In other words, all babies from the above cross must be either banana males or normal females.
But breeding results say that a normal male and a banana female produce normal males, normal females, banana males and banana females. So banana cannot be Z linked.
I know this has nothing to do with male maker and female maker males. But the above mating is the easiest way to prove that a gene is not Z linked.
As for multiple sex chromosomes, I will wait for someone to count the chromosomes before I am convinced.
Re: Is banana/coral glow sex linked?
As for the question of super bananas. If banana was Z linked, then only males could be super bananas. Because by definition, a super banana has two banana genes. One would be in one Z chromosome and the other is in the second Z chromosome of the male. As a female has only one Z chromosome, she has only one banana gene.
