Question about sex-linked punnets

[RamsFan1991]

So when would I use a dominant and recessive letter for sex-linked questions over just one letter?

Ex: Found them from Bootcamp Test #2 and #1 for Biology respectively.

For the first one, why is the hemophiliac woman carrier xh x while in the second one the hemophiliac woman carrier is xH xh? So confusing!

So if xh x is considered a woman carrier, would xh y be a male carrier?
This is my current understanding:

xH xH = no disease
xH xh = carrier for disease
xh xh = have disease
xH y = no disease
xh y = have disease

However, the first question is saying

xh x = carrier

so would that make
xh y = carrier?

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[shaidester]

I think your example of xh x and xy is one where they omit the dominant allele. So, anywhere that has an absence of an allele is implied a dominant. It's kind of like a shortcut thing but it can be confusing sometimes. I wouldn't be worried about it on the actual test though, most questions involve you setting up the punnett square so you could set it up anyway you want.

I could be wrong though. Genetics was my least favorite thing in biology. Wait for someone else's reply to confirm what I said.

 

[BobbyBeavis]

I am confused by your example, but let me give you one:

Hemophilia, the X-linked Recessive gene.

Say Susie has a Dad with Hemophilia and a Mom that is perfectly normal with no signs of Hemophilia in her family. Susie marries Richard that also has a family tree with no hemophilia present.

Since you receive an X from mother and either X or Y from father, Susie will have XhX. The Father had to donate his X chromosome to produce Susie, and the only X he was able to give was the one infected with the hemophilia trait. Richard, with no hemophilia in his family tree, will be XY.

So if Susie, (XhX) reproduces with Richard (XY), they can effectively produce:

XhX
XhY
XX
XY

50% chance for their sons to have hemophilia
50% chance for their daughters to be a carrier for hemophilia, as their mother was.