If he marries a genotypically normal girl what are the chances that they'll have an affected baby?

a- 30%

b- 25%

c- 50%

d- 100%

e- Can't be predicted

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If he marries a genotypically normal girl what are the chances that they'll have an affected baby?

a- 30%

b- 25%

c- 50%

d- 100%

e- Can't be predicted

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625 Posts

I agree, but can someone explain the significance of the uncle?

Hemoglobin H is the only evidence that it's alpha thalassemia and not any other hemoglobinopathy.I agree, but can someone explain the significance of the uncle?

By the way answer given by yanlin is wrong

think of it more

What is the answer then? Please ..Hemoglobin H is the only evidence that it's alpha thalassemia and not any other hemoglobinopathy.

By the way answer given by yanlin is wrong

think of it more

because the parents of our patients had a stillborn with hydrops fetalis it means that they must both have the alpha genes in cis-configuration --,--/a,a.

So our patient must have got --,--/a,a as he has no Heinz bodies (so he's alpha thalassemia minor which means he got one normal allele from one parent and another cis-deleted allele from another parent)

So our patient has a 50% chance of giving the abnormal alleles and 50% chance of giving the normal alleles.

can someone show me the math here pls? I dont get the 50% unless it was an AD disorder, but as thalassemia is AR I come up with the same 25%

because the parents of our patients had a stillborn with hydrops fetalis it means that they must both have the alpha genes in cis-configuration --,--/a,a.

So our patient must have got --,--/a,a as he has no Heinz bodies (so he's alpha thalassemia minor which means he got one normal allele from one parent and another cis-deleted allele from another parent)

So our patient has a 50% chance of giving the abnormal alleles and 50% chance of giving the normal alleles.

I've already explained that!can someone show me the math here pls? I dont get the 50% unless it was an AD disorder, but as thalassemia is AR I come up with the same 25%

You need to review the alpha thalassemia genetics. It's AR but it's with 4 alleles and cis or trans configuration.

Our patient is having cis- configuration deletion in one of his chromosomes. Which means whenever he gives that configuration his babies are going to be thalassemia minor also.

The chance of producing a thalassemia major baby is zero because his wife is genotypically normal.

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