Genetics prob from book that I cant get (probability type)
(I got an answer different than the solution manual and I feel they did it wrong)
Background info: Every person has 2 alleles that can be H or h. This is a dominant allele problem, so that means a person needs just one H to have the disease (ie. HH, hH and Hh have the disease while hh does not).
OK... guys father has the disease, and is Hh, and his mother doesnt have the disease (hh). (every person gets 1 allele from each parent, at random)...so, right there, there is a 50:50 chance he has the disease (Hh or hh)
But, the disease has a late life onset. There is a 2/3 chance that someone who is fifty will have shown the symptoms IF they have the disease.
What is the probability that this person has the disease given that they are 50 and have no symptoms of the disease?
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