sex linkage question

[joonkimdds]

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I was going over sex-linkage and found out that
XcY = colorblind male
XcX = female who carries colorblindness but she is not colorblind

ok so this means female has to have two of the same X to be what it means to be otherwise that female is just a carrier, right?

I did several problems and it all maked sense except couple of them.

it was a problem between brown eye and green eye
and XbXg female has brown eye because brown is dominant over green
but shouldn't she have XbXb to be brown color eye even if b is dominant?

 

[Fariba]

I was going over sex-linkage and found out that
XcY = colorblind male
XcX = female who carries colorblindness but she is not colorblind

ok so this means female has to have two of the same X to be what it means to be otherwise that female is just a carrier, right?

I am not quite sure I understand your question, but here is what I know. The only way a woman becomes colorblind is if her carrier mother and colorblind father each pass on the recessive X allele.

I did several problems and it all maked sense except couple of them.
it was a problem between brown eye and green eye
and XbXg female has brown eye because brown is dominant over green
but shouldn't she have XbXb to be brown color eye even if b is dominant?

For a dominant allele, the genotype can be either homozygous dominant, or heterozygous - the dominant phenotype will always be expressed.

 

[DMD to Be]

I think the second problem w/ the brown/green eyes is an autosomal problem - not a sex-linked one. Brown is dominant over all other eye colors, so a male or female with one allele for brown eyes regardless of the other will have brown eyes.

 

[joonkimdds]

I think the second problem w/ the brown/green eyes is an autosomal problem - not a sex-linked one. Brown is dominant over all other eye colors, so a male or female with one allele for brown eyes regardless of the other will have brown eyes.

how do i know which one is sex linkage and which one isn't?
This problem stated that this color woman marry this color man and how many brown and green color children r there blah blah.

 

[tinman831]

how do i know which one is sex linkage and which one isn't?
This problem stated that this color woman marry this color man and how many brown and green color children r there blah blah.

You should give us the actual problem in order for us to help you. Otherwise, all we can do is make assumptions as to what the answer could be.

 

[fancymylotus]

women have 2 x's,which is why the rec trait has to be on both for it to show up. men only have one,so if they carry the trait,they show it. brown eyes are dominant to green eyes in general...i think youre asking two diff questions.

 

[djeffreyt]

First, eye color is usually not sex linked.

I'm not saying it couldn't be sex-linked, but it usually isn't. That being said, the example you give with XbXg, is sex-linked, because your showing Xs and Ys carrying the alleles.

The reason a person with XbXg is brown eyed when Brown is dominant is because when you have a dominant allele, it masks the phenotype of the recessive allele. You only need one dominant allele to produce the brown phenotype...that is the definition of dominance.

 

[joonkimdds]

You should give us the actual problem in order for us to help you. Otherwise, all we can do is make assumptions as to what the answer could be.

I really want to do that and that's what I usually do but the author who made the book with this problem doesn't want me to reveal any of his problems on SDN and that's why... 🙁

 

[Notoriousjae]

doesnt want u to reveal any of his problems? no sharing=no caring. chuck the book in the trash.

 

[DMD to Be]

how do i know which one is sex linkage and which one isn't?
This problem stated that this color woman marry this color man and how many brown and green color children r there blah blah.

Hm, in genetics I learned which traits are sex-linked and which were not. Actually had to memorize all of them, and that class was hardcore....which I suppose is why I know my genetics now. 😀