Question

In your job as a genetic counselor, you interview a man recently diagnosed with Huntington's disease. He asks you about the probability that his daughter has inherited this disease? What do you say?

Answer 1

As a genetic counselor, I would inform the man that as an autosomal dominant disorder, Huntington's disease has a 50 percent chance of being passed on to his daughter. Using a Punnett square can illustrate this inheritance pattern, showing the risks involved with each pregnancy.

Step-by-step explanation:

Genetic Counseling and Huntington's Disease

When you are diagnosed with Huntington's disease and you inquire about the likelihood that your daughter has inherited this condition, as a genetic counselor, I would explain that Huntington's disease is an autosomal dominant disorder. This means that if a parent has the disease, there is a 50 percent chance of passing the mutated gene on to each child. The faulty gene causes the brain's cells to deteriorate, leading to symptoms such as muscle spasms and personality changes, typically manifesting in middle age.

To visualize this, a Punnett square can be used to predict inheritance patterns. If we represent the dominant Huntington allele by 'H' and the normal allele by 'h', a parent with Huntington's disease (Hh) has a 50 percent chance of passing the 'H' allele to their offspring. Thus, there's a 50 percent chance that a child will inherit Huntington's disease from a parent who carries the gene.