Module 12: Hereditary Cancer Syndromes

Question 1

Variable Expression

Answer 1

• Individuals with the mutation in the same gene can express the condition differently
• Can be dependent on age, gender, and environment

Question 2

Reduced Penetrance

Answer 2

Some individuals with a mutation will never express the condition (all or none)

Question 3

De Novo Mutation

Answer 3

Mutations new to the individual and not shared with their parents or other family members

Question 4

What genes cause inherited breast cancer?

Answer 4

• BRCA 1
• BRCA 2
• Other rare syndromes with other associated cancers

Question 5

HBOC Syndrome

Answer 5

• Autosomal dominant
• Tumor suppressor genes
• Males can pass the gene on to their daughters
• Not all women that carry the gene will develop cancer, but they can pass it on to their children

Question 6

Familial Adenomatous Polyposis (FAP)

Answer 6

• APC gene
• Autosomal dominant tumor suppressor gene
• Can be de novo or somatic mosaicism
• Fully penetrant (100% risk of cancer)

Question 7

Hereditary Nonpolyposis Colon Cancer (HNPCC)

Answer 7

• Autosomal dominant
• AKA Lynch Syndrome
• 75% cancer risk

Question 8

What causes inherited cancers to present at an earlier age of onset?

Answer 8

The inherited mutation is in every cell in the body

Question 9

(T/F) Reduced penetrance is a common finding in many, but not all cancer syndromes

Answer 9

True

Question 10

What principle of Hardy-Weinberg is violated in the Ashkenazi Jewish population to cause a founder mutation?

Answer 10

Large population

Question 11

What additional types of cancer has been associated w/ BRCA 1 & 2 mutations?

Answer 11

• Prostate
• Melanoma
• Pancreatic

Question 12

What is non-colon finding in some people with FAP?

Answer 12

CHRPE

Question 13

What is the classification of the gene that causes Hereditary Nonpolyposis Colon Cancer (HNPCC)?

Answer 13

Mismatch repair gene