Deck 25: Medical Genetics and Cancer

Question 1

Select the statements that are associated with an autosomal dominant pattern of inheritance. Check all that apply.

A) An affected offspring has one or more affected parents.
B) An affected offspring has two unaffected parents.
C) An affected individual with one affected parent will have 50% of its offspring affected.
D) Two affected heterozygous individuals will have 25% of their offspring unaffected.

Answer 1

A, C, D

Question 2

Select the events that can convert a proto-oncogene into an oncogene. Check all that apply.

A) Viral integration near the proto-oncogene
B) Missense mutations
C) Translocation
D) Aneuploidy
E) Gene amplification

Answer 2

A, B, C, E

Question 3

The majority of human cancers are caused by ________.

A) viral infections
B) inherited mutations
C) spontaneous mutations
D) carcinogens

Answer 3

D

Question 4

The first acutely transforming virus to be isolated was ________.

A) RSV in chickens
B) Hepatitis B in humans
C) SSV in monkeys
D) ALV in mice
E) SV40 in humans

Question 5

When are caspases active?

A) The normal cell cycle
B) Apotosis
C) Viral integration
D) DNA replication

Question 6

In the analysis of a family, you notice that males are more likely to contract a certain disease and the daughters of affected males produce 50% of their sons affected with the disease. This disease is displaying what pattern of inheritance?

A) X-linked recessive
B) Autosomal recessive
C) Autosomal dominant
D) X-linked dominant

Question 7

In a disease that is caused by a single gene, the concordance among monozygotic twins should be ________.

A) 0%
B) 25%
C) 50%
D) 75%
E) 100%

Question 8

You are analyzing a human pedigree for a new disease and discover that the disease occurs with the same frequency in both sexes and that 25% of the children from two unaffected heterozygous parents have the disease. This disease is displaying ________ inheritance.

A) autosomal recessive
B) autosomal dominant
C) sex-linked recessive
D) sex-linked dominant

Question 9

Prions can contain either DNA or RNA as their genetic material.

Question 10

When GTP is bound to Ras, it is in the ________ form.

A) active
B) inactive

Question 11

An oncogene form of Ras would have ________.

A) decreased GTPase activity
B) an inability to bind GTP
C) increased susceptibility to growth factors
D) inability to bind Raf-1

Question 12

Which test provides the earliest indication of genetic problems in a fetus?

A) Amniocentesis
B) Chorionic villus sampling
C) Both provide reliable indications at the same stage of development

Question 13

What prion conformation may result in a prion-related infection?

A) PrPSc
B) PrPC
C) Both can cause disease

Question 14

Select the factors that would indicate that a disease had a genetic, rather than an environmental, cause. Check all that apply.

A) The disease spreads from person to person.
B) The disease has a specific age of onset.
C) There is a high level of the disease's concordance among monozygotic twins.
D) The disease does not spread to people sharing similar environmental situations.

Question 15

What diseases are caused by prions? Check all that apply.

A) Phenylketonuria
B) Creutzfeldt-Jacob disease
C) Gerstmann-Straussler-Scheinker disease
D) Familial fatal insomnia

Question 16

Chronic myelogenous leukemia is an example of a proto-oncogene activation by ________.

A) Action of a virus
B) Missense mutation
C) A translocation
D) Gene amplification
E) None of the answers are correct

Question 17

The term that indicates that cancer has begun to migrate to other parts of the body is ________.

A) malignant
B) benign
C) metastatic
D) invasive
E) clonal

Question 18

In a disease that is associated with a single recessive allele, the concordance among dizygotic twins should be ________, assuming both parents are heterozygous carriers.

A) 0%
B) 25%
C) 50%
D) 75%
E) 100%

Question 19

A gene that promotes the development of cancer is called a(n) ________.

A) clone
B) tumor suppressor gene
C) mutagen
D) carcinogen
E) oncogene

Question 20

What is p53?

A) A caspase
B) A proto-oncogene
C) A transcription factor
D) A tumor-suppressor gene
E) None of the answers are correct

Question 21

The process of ________ removes amniotic fluid from a pregnant mother to examine fetal cells for genetic problems.

A) amniocentesis
B) chorionic villus sampling
C) preimplantation genetic diagnosis
D) in vitro fertilization

Question 22

A pedigree analysis is the study of family trees to establish patterns of inheritance.

Question 23

Dizygotic twins share ________ of their genetic information.

A) 25%
B) 50%
C) 75%
D) 100%

Question 24

How can a tumor suppressor gene lose its function? Check all that apply.

A) Gene mutation
B) Duplication
C) Aberrant DNA methylation
D) Aneuploidy leading to loss of the tumor suppressor gene

Question 25

In the United States, most newborns undergo a test for primary congenital hypothyroidism, a condition where people are unable to produce enough thyroid hormone. On a nationwide basis, this is an example of

A) genetic testing.
B) genetic screening.
C) amniocentesis.
D) preimplantation genetic diagnosis.

Question 26

DNA damage is sensed by E2F at the G1 and G2 checkpoints.

Question 27

A disease that can be caused by mutations in different genes is said to have homogeneity.

Question 28

After genetic testing, a person is identified with an inherited mutation associated with a specific class of cancer. Select the statements that are true about this person. Check all that apply.

A) The person will definitely develop cancer in his or her lifetime.
B) The person is predisposed to the development of cancer.
C) The mutation is probably in a tumor suppressor gene.
D) The person may pass the trait on to his or her offspring.

Question 29

Checkpoint proteins are encoded by ________.

A) oncogenes
B) growth factors
C) proto-oncogenes
D) tumor-suppressor genes

Question 30

An oncogene may promote cancer by keeping the cell growth pathway in the off position.

Question 31

A ________ is a cellular gene that has the potential to become an oncogene.

A) carcinogen
B) proto-oncogene
C) tumor-suppressor genes
D) caspase gene

Question 32

Select the events that must occur for inherited retinoblastoma to develop. Check all that apply.

A) An individual must have two mutated copies of the Rb gene.
B) The p53 gene must be mutated.
C) E2F is no longer regulated by Rb.
D) The cell proceeds uncontrolled through cell division.

Question 33

You are working in a lab where you are studying a disease that is known to be caused by a single nucleotide change, although the effect this change ultimately has on the protein's structure/function is unknown. You have DNA samples from multiple patients that you suspect of having this disease. What is the most efficient way to test the samples for the relevant mutation?

A) Western blotting
B) DNA sequencing
C) Karyotyping
D) Amniocentesis

Question 34

The general approach in which researchers and clinicians use methods that enable them to understand the molecular changes that occur in diseases such as cancer is called ________.

A) molecular profiling
B) personalized medicine
C) DNA microarrays
D) cluster analysis

Question 35

Herceptin is a drug that is given to treat certain breast cancers. However, it is most effective on tumors that are overexpressing HER2. Therefore, patients are tested for HER2 overexpression before being given Herceptin. This is an example of

A) concordance.
B) a haplotype.
C) personalized medicine.
D) karyotyping.

Question 36

The age at which a disease appears in an organism is called the ________.

A) null age
B) critical age
C) age of incubation
D) age of onset

Question 37

Cancer is considered clonal because daughter cells from a cancer cell have the same genetic makeup as the parent cell.

Question 38

Programmed cell death is called genome maintenance.

Question 39

Indicate the roles of growth factors in the cell cycle. Check all that apply.

A) They act as repair proteins that fix DNA damage in the cell.
B) Growth factors bind to a receptor and initiate a signal cascade in the cell.
C) Their binding changes gene transcription.
D) They allow the cell to progress through the cell cycle.

Question 40

An environmental agent that causes cancer is called a ________.

A) carcinogen
B) malignant agent
C) invasive agent
D) metastatic agent

Question 41

Haplotypes between homologs in the same individual ________; haplotypes for the same chromosome in different individuals ________.

A) are always the same; are always different
B) can be the same or different; can be the same or different
C) are always the same; can be the same or different
D) can be the same or different; are always different

Question 42

When a scientist is attempting to use haplotype analysis to link a disease-causing allele to a molecular marker, it is important for the marker to be close to the disease-causing allele, otherwise ________ may occur.

A) additional mutation
B) crossing over
C) linkage disequilibrium
D) founder effect