Homework SourseHuntington disease is an autosomal dominant disease Two pare
Huntington disease is an autosomal dominant disease. Two parents are each Aa( they have the disease). What is the probability that their FIRST child will be female and affected? Please explain this answer. *** ( the answer shown is correct.the answer is not 3/8)!
What is the probability that their first child is a female and affected with HD? 34 points) PCHD- 1-P(norma x (2/3) x (1/4)- 1-1/9 8/9 88.9% or you can do: POHD) (113) x (13) x 1+(2/3) x (13) x 2+(2/3) x (2/3) x (3/4) 8/9 88.9% PODaughter and HD): (8/9) x (1/2) 4/9 44.4% Solution
In autosomal dominant disease, each dominant allele carries the gene for disease expression. So, If both parents are affected, there are 75% chances of immediate offsprings to get the disease.
Aa x Aa --------> AA (Boy), Aa(Girl), aA (Boy), aa (Girl)
The probability of getting disease is in AA, Aa and aA , that is 75%
Probability of having a girl child is 1/2, that is 50%
