03/15g Genetic Mechanisms of Pathology I

Question 1

What are the classic symptoms of familial hemochromatosis?

Answer 1

Diabetes mellitus

Cirrhosis

Skin pigmentation

Usually presents in middle age

Question 2

What are the inheritance mechanisms of familial hemochromatosis?

Answer 2

Autosomal recessive

Male predominance

Carrier frequency in Caucasians is 10%

Due to a mutation in the HLA-H gene on Chr. 6

Question 3

What are the typical symptoms of cystic fibrosis?

Answer 3

Bronchiectasis

Pancreatic insufficiency

Male infertility

Hepatic biliary cirrhosis

Question 4

What are the inheritance mechanisms of cystic fibrosis?

Answer 4

Autosomal recessive Results from mutations in the CFTR gene Many different types of mutations - most common mutation is the delta-F508 mutation, but it only accounts for 65% of cases Most common lethal genetic disease in the US - carrier frequency is 2-4%

Question 5

What is the inheritance mechanism of Factor V Leiden?

Answer 5

Autosomal dominant

Question 6

What are the results of a mutation in Factor V?

Answer 6

Mutation inhibits the ability of protein C to inactivate factor V This results in an increased risk of spontaneous thrombosis