A man & woman with normal vision have a color-blind son. Whats' the chance their daughter will be color blind?

Question

How does a sex related trait such as color blindness effect offspring. Why do men inherit this disease more than woman?

Answer 1

Men are either color blind or not. Women can be color blind, not, or carriers. Since the father is not color blind, he is innocent of the son's color blindness. It is his mom's fault. She is not colorblind, so she is a carrier. The only way a girl can be color blind is if both of her X's are coded for color blind. She has a 50% chance of having no traits for color blindness and 50% chance of being a carrier. There is no chance of having a color blind daughter.

Now, if they have another boy... there is a 50% chance of him not being color blind, and a 50% chance of him being colorblind. This is due to the fact that boys are XY. Colorblindness is carried on the X chromosome.

Now, a little help for both boy and girl. "c" will be the colorblind trait.

XY- not colorblind boy
XcY - colorblind boy
XX - not colorblind girl
XcX - carrier girl
XXc - carrier girl
XcXc - colorblind girl

The mom you refer to is XcX.
The dad you refer to is XY.
There are 4 possible results:
XcX, XcY, XX, XY
as you can see...
25% carrier girl
25% colorblind boy
25% no colorblind girl
25% no colorblind boy

How is that?

Answer 2

There will be zero chance of the daughter being color blind, although she might end up being a carrier of the trait. The gene is carried on the X chromosome, of which men only have one. Therefore, men cannot be carriers, they can only be color blind or not color blind. Since women carry two X chromosomes, they can have one carry a the defective gene for colorblindness and one normal copy, and still not be color blind, since they have one working copy. To produce a color blind daughter, the man would have to be color blind, and the woman would have to at least be a carrier, that would give 50-50 odds of a daughter who was color blind.

Answer 3

There is (nearly) no chance their daughter will be color-blind, because the characteristic is linked to the X chromosome. Since the father is not color-blind, his X does not carry the trait. Since a daughter would inherit an X from each parent, and the trait needs to be carried on both X's to manifest.
Since males have only one X (from the mother), their chances of manifesting recessive sex-linked traits is 1 in 2.
Blue-yellow colorblindness is much more rare, and not sex-linked; it is about equally distributed between the sexes.

Answer 4

it depends whose is heterozygous for the trait if one heterozygous Hh (h) represents defective trait and the other is homozygous HH then the chance the offspring would be colorblind is 75-25 or 4-1 odds that the child will have normal vision. the easiest way like someone else said is to do a punnett square though. draw a square with one line going down and one line going across so u should have 4 boxes then just put any alleles in whichever box doesnt matter cuz the result'll be the same... hope this helps.

Answer 5

Well that father has normal traits/genes...and the mother is a carrier. Use the Punnette Square. It helps. If the mother is a carrier, and the father is just plain normal, the chances of her daughter being a color-blind patient would be 0. The dauther has two possiblities: Normal, or carrier.

Answer 6

Responder tpjunkie is correct. From the statement of the problem, Dad has a good X and a good Y; Mom has a good X and a bad X. Son got Dad's good Y but Mom's bad X. Daughter will get a good X from Dad, and possibly (50/50) a bad one from Mom, but you need only one good X to carry the genes for color vision.
This explains why males get colorblindness more often: they have only one X, and if it's bad, they lose, while females, having two X-es, don't lose unless BOTH X-es are bad.

Answer 7

it all depends on what the traits are. if the father is colorblind, then his son has a fifty percent chance to be colorblind, and his daughter will have a fifty percent chance to be a carrier of the trait.

Answer 8

the man receives xy- chromosomes, so the only x chromosome he has is the gene for being color blind and the y chromosome can not fill in the discrepancies of the x- chromosome, so the males are color blind

Answer 9

If I was there with you I'd teach you Punnett squares. It's futile to attempt to do it online.
Father has normal vision. They can produce carrier daughters, but not colorblind daughters.

Answer 10

because the trait for colorblindness is a dominate trait for guys and for girls its a recessive gene