Hemophilia A is an X-linked recessive disease. If a mother without the disease and a father without the disease have one son diagnosed with hemophilia, what is the probability that a future daughter they have together will also be afflicted with hemophilia?
%
The probability that a future daughter from the same parents will be afflicted with hemophilia is 0%.
Hemophilia A is an X-linked recessive disease, which means the gene mutation for the disease is located on the X chromosome. In males, who have one X and one Y chromosome, a single copy of the mutated gene will result in the disease, as they do not have another X chromosome to compensate for the mutation.
In females, who have two X chromosomes, they would need to have the mutated gene on both X chromosomes to be affected by the disease. In this case, the mother does not have the disease, which means she does not have the mutated gene on any of her X chromosomes. The father also does not have the disease, indicating he does not have the mutated gene either.
Since both parents do not have the mutated gene, they cannot pass it on to their daughter. Therefore, the probability of a future daughter being afflicted with hemophilia is 0%.