Genetics Lecture 7 - Clinical DNA Diagnosis

Question 1

Define haploinsufficiency. What inheritance pattern do these diseases with haploinsufficiency follow?

Answer 1

Haploinsufficiency is when half the normal protein is not sufficient for normal function. It is inherited in an autosomal dominant fashion, but has incomplete dominance.

Question 2

Name an example of haploinsufficiency.

Answer 2

Familial hypercholesterolemia.

Question 3

What is meant by a dominant negative loss of function? Name an example of this.

Answer 3

The mutant protein interferes with normal protein function. Example: Osteogenesis imperfecta - the mutant collagen disrupts collagen polymerization and wrecks everything.

Question 4

Name a gain of function disorder. What inheritance pattern do these disorders follow?

Answer 4

Achondroplasia. Autosomal dominant.