The Difference in Mode of Inheritance Between Huntington Disease and Cystic

Question

The difference in mode of inheritance between Huntington disease and cystic fibrosis is that
A) Huntington disease only affects men and cystic fibrosis affects both sexes.
B) Huntington disease skips generations and only affects children, whereas cystic fibrosis can strike at any age and never skips generations.
C) Huntington disease does not skip generations but cystic fibrosis can.
D) A person with Huntington disease can have unaffected parents, but a person with cystic fibrosis must have an affected parent.
E) Huntington disease affects females and cystic fibrosis affects males.

Accepted Answer

Huntington disease is an autosomal dominant disorder, meaning it does not skip generations; if a parent has the disease, there is a 50% chance of passing it to offspring. Cystic fibrosis is an autosomal recessive disorder, which can skip generations if both parents are carriers but not affected.