genetics

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spoog74

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Steve and Anna are both carriers for a non-lethal, autosomal, recessive condition. What is the probability that their first child will be a carrier for the condition?


The answer is 50 % but i dont see why its not 75 % .. Isnt having the condition considered being a carrier?
 
Steve and Anna are both carriers for a non-lethal, autosomal, recessive condition. What is the probability that their first child will be a carrier for the condition?


The answer is 50 % but i dont see why its not 75 % .. Isnt having the condition considered being a carrier?

No.

having the disease is having the disease. being a carrier is one who does not have the disease but their offspring might.
 
Their genotype both be Xx since they are carriers. Therefore the kid would need to have Xx as his genotype to carry it... with the punnett square the kid would have:

XX- does not carry or express the gene
2 Xx- Carries the gene
xx- expresses the gene

Expressing is different from carrying.
 
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