1. a man and woman are both affected with the brca1 gene for familial breast cancer, a disease that has 80% penetrance in all in
dividuals who carry the allele. they are both heterozygotes for the disease-causing mutation. what is the probability that they will have a phenotypically normal child?
The probability to have a phenotypically normal child will be 40% because parents are both heterozygotes for this disease-causing mutation that has 80% penetrance.
<h3>What is genetic penetrance?</h3>
The expression genetic penetrance refers to the chances of expressing a given phenotype which may be associated with both genetic and environmental factors.
In conclusion, The probability to have a phenotypically normal child will be 40% because parents are both heterozygotes for this disease-causing mutation that has 80% penetrance.
