A 30yearold man is scheduled for genetic counseling because his maternal uncle recently died with Huntington disease. The man's mother died in a car accident at age 25. Which of the following should the counselor ask to BEST assess the patient's risk of developing HD?
A. if any of the uncle's children have developed HD
B. the age at which the uncle began having symptoms of HD
C. the severity of the uncle's HD symptoms
D. if the patient has experienced episodes of memory loss