Deck 20: Genetic Testing and Treatment

Question 1

One of the first applications of pharmacogenetics in prescribing drugs is for

A)Accutane,an acne drug.
B)an early pregnancy test kit.
C)warfarin,a blood thinner.
D)a narcotic to treat chronic pain.

Answer 1

C

Question 2

One of the most important types of information that a patient can bring to an initial appointment with a genetic counselor is

A)her immunization records from childhood.
B)results of a comprehensive lipid profile.
C)the family health history,extending to second degree relatives.
D)a list of the occupations of every family member.

Answer 2

C

Question 3

"Preconception comprehensive carrier screening" is a test that detects heterozygotes for nearly 500 single-gene diseases affecting children.

Answer 3

True

Question 4

Newborn screening using mass spectrometry identifies certain single-gene disorders by detecting

A)the causative mutation.
B)the wild type gene sequence.
C)an unusual metabolite or metabolic imbalance.
D)abnormal proteins in urine.

Question 5

The Genetic Testing Registry of the U.S.National Institutes of Health acts as a clearinghouse to provide information on genetic tests.

Question 6

Newborn screening reveals that newborn Jessica has inherited phenylketonuria (PKU).Her parents are distraught at the diagnosis,but a nutritionist explains that Jessica can be treated,right away.The treatment for PKU is

A)nonheritable gene therapy.
B)heritable gene therapy.
C)exchange of her blood supply.
D)dietary.

Question 7

Which of the following might a genetic counselor do as part of her job?

A)Order prenatal tests,interpret the results,and then deliver the baby
B)Order a lipid profile,interpret the results,then prescribe a statin drug if cholesterol levels are unhealthy
C)Require a patient to take a test for hereditary colon cancer
D)Explain the inheritance of a specific disorder in a family,evaluate risks for relatives,and advise on genetic testing

Question 8

Genetic counseling to help patients with Huntington disease in their families decide if they wish to be tested

A)explains that testing for adult-onset dominant disorders is not available.
B)takes one or two visits.
C)takes several months.
D)advises all such individuals not to have children.

Question 9

Maxwell needs to take an anti-depressant drug.He enrolls in a clinical trial to detect genetic variants and gene expression profiles associated with response to various drugs.This approach to selecting a therapeutic drug is called

A)pharmacogenetics.
B)pharmacogenomics.
C)pharmacology.
D)recombinant DNA technology.

Question 10

Enzyme replacement therapy treats

A)the genotype.
B)the genome.
C)the phenotype.
D)the genetic code.

Question 11

Macy has BRCA1 breast cancer.Her sister Philene is healthy,but wants to know if she has inherited the BRCA1 mutation that could make her develop cancer.She is a candidate for a

A)newborn screen.
B)carrier test.
C)genome screen.
D)genome-wide association study.

Question 12

Nondirective genetic counseling

A)does not accept health insurance.
B)does not deal with disorders carried on the sex chromosomes.
C)considers diseases caused by genes that are located throughout the genome.
D)offers options but not opinions.

Question 13

The field of genetic counseling began when the term was coined

A)in 1986,when the human genome project was first suggested.
B)in 1947,to help physicians explain inherited diseases to their patients.
C)in 1953,when Watson and Crick discovered the structure of DNA.
D)in 1865,when Gregor Mendel published his work on inheritance patterns in pea plants.

Question 14

A genetic counselor might discuss assisted reproductive technologies with a couple who wish to

A)adopt a child.
B)avoid passing on a disease-causing allele to a child.
C)avoid cancer in their children.
D)have a child who will excel at a particular sport or have a particular talent.

Question 15

Unlike cholesterol checks and chest x-rays,the results of genetic tests may have repercussions to family members who share genotypes that can affect health.Learning Outcome: 20.02 Describe types of genetic tests that are done at different stages of human prenatal development and life.

Question 16

Diagnosis of hereditary hemochromatosis cannot be based on the results of a genetic test alone because

A)the disease is incompletely penetrant.
B)genetic tests are untrustworthy.
C)the disease is genetically heterogeneiC.
D)the disease is not inheriteD.

Question 17

A test offered on the Web by a direct-to-consumer genetic testing company genotypes a gene for ability to taste bitter substances.This test is not regulated by the Clinical Laboratory Improvement Amendments (CLIA)because

A)the test is not expensive.
B)the test provides information,not a diagnosis.
C)the test is offered in a state of the U.S.not covered by these regulations.
D)the Genetic Information Nondiscrimination Act outlawed CLIA.
E)it is not accurate.

Question 18

Sheree is referred to a genetic counselor because a cystic fibrosis (CF)test done as a routine part of her prenatal care indicated that she is a carrier of the most common mutant allele.Sheree is stunned,because no one in her family has the disease.She is 26 years old.The genetic counselor would most likely

A)explain autosomal recessive inheritance and suggest that Sheree's husband be tested for CF.
B)explain autosomal dominant inheritance and suggest that Sheree's husband be tested for CF.
C)explain autosomal recessive inheritance and suggest that Sheree's parents be tested for CF.
D)advise Sheree to have amniocentesis to check the fetus for the CF genotype.

Question 19

"Patients-in-waiting" are false positives whose newborn screening reveals disease markers,but never develop the predicted symptoms.

Question 20

Rita has been diagnosed with HER2 breast cancer,and is prescribed Herceptin.The approach of basing a drug prescription on the results of a single-gene test is called

A)pharmacogenetics.
B)pharmacophenetics.
C)pharmacogenomics.
D)enzyme replacement therapy.

Question 21

In substrate reduction therapy,a drug taken by mouth decreases the amounts of the molecule on which a deficient enzyme acts.

Question 22

Which is an example of a germline gene therapy?

A)A transgenic plant or animal
B)A bone marrow transplant
C)A disabled cold virus that delivers genes to airway epithelium to treat cystic fibrosis
D)Removing skin cells,genetically altering them,and replacing them

Question 23

A serious limitation of using a retrovirus as a vector for gene therapy is that

A)the retrovirus may insert into a proto-oncogene,causing cancer.
B)a genetically modified retrovirus causes AIDS.
C)it causes ADA accumulation.
D)reverse transcriptase will not work in human cells.

Question 24

Leber congenital amaurosis type 2 has been successfully treated using gene therapy.

Question 25

Performing gene therapy on somatic cells removed from the body and then returning these cells to the body is called _____ gene therapy.

A)in vivo
B)in situ
C)in vitro
D)ex vivo

Question 26

Reginald receives a stem cell transplant to treat a blood cancer,multiple myeloma.His treatment is an example of

A)germline gene therapy.
B)heritable gene therapy.
C)somatic gene therapy.
D)in vitro fertilization.

Question 27

A patient received bone marrow modified by an adeno-associated virus (AAV)carrying a human gene that encodes an enzyme her body could not make.This is an example of

A)protein therapy.
B)germline gene therapy.
C)somatic gene therapy.
D)retroviral gene therapy.

Question 28

Which of the following would provide the longest lasting treatment for Leber's congenital amaurosis II?

A)Replacing an enzyme that restores the function of T and B cells
B)Substrate reduction therapy and pharmacological chaperone therapy
C)Injecting adeno-associated virus carrying ornithine transcarbamylase (OTC)into T and B cells
D)Injecting adeno-associated virus carrying a wild type version of the RPE65 gene into affected cells of the retina

Question 29

Using gene therapy to correct ornithine transcarbamylase deficiency (OTC)would prevent buildup of _____ in the blood.

A)cholesterol
B)RNA
C)adenosine deaminase
D)ammonia

Question 30

Repurposing a drug is much more economical than developing a new one.

Question 31

Which of the following is a vector used to deliver genes in human gene therapy?

A)Parvovirus
B)Rabies virus
C)Adeno-associated virus
D)E.coli

Question 32

Introducing a gene in a liposome to carry DNA across the plasma membrane is a(n)_____ gene therapy.

A)in situ
B)ex vivo
C)in vivo
D)ex hubris
E)et al

Question 33

Many children born with ornithine transcarbamylase deficiency (OTC)die within seventy-two hours of birth.Jesse Gelsinger was not diagnosed with OTC until he was two because _____ and therefore his symptoms were milder.

A)his defective gene was autosomal recessive
B)he was a mosaic
C)of X-inactivation in males
D)of parental imprinting

Question 34

Which of the following would provide the longest lasting treatment for adenosine deaminase (ADA)deficiency?

A)Using siRNA to knockdown ADA genes
B)Using cDNA to produce ADA in
C)Receiving white blood cells genetically modified to carry functional ADA genes
D)Injecting cloned human adenosine deaminase (ADA)purified from a cow
E)coli

Question 35

Germline gene therapy would correct a genetic defect in

A)an unaffected individual and his or her offspring.
B)an affected individual and all of his or her descendants.
C)the parents of an affected individual.
D)the unaffected sibling of an affected individual.

Question 36

Adenosine deaminase (ADA)deficiency results in

A)hereditary emphysemA.
B)neurotransmitter imbalances.
C)severe combined immune deficiency.
D)chronic myelogenous leukemia.

Question 37

A nasal spray for cystic fibrosis patients,which contains adenovirus particles carrying a normal human CFTR gene,is an example of

A)ex vivo gene therapy.
B)in situ gene therapy.
C)in vitro gene therapy.
D)in vivo gene therapy.

Question 38

Tyrone has Gaucher disease.He receives recombinant glucocerebrosidase every other week in an infusion to prevent the symptoms.This treatment is an example of

A)gene therapy.
B)gene transfer.
C)enzyme replacement therapy.
D)pharmacological chaperone therapy.
E)substrate reduction therapy.

Question 39

Pharmacological chaperone therapy

A)restores proper folding to a misfolded protein.
B)restores the double helix to opened-up DNA.
C)restores the sugar-phosphate background to the DNA of a specific gene.
D)replaces a missing enzyme.

Question 40

Nonheritable gene therapy is performed on _____ cells.

A)germline
B)somatic
C)bacterial
D)gametic

Question 41

The defect in Canavan disease that causes the symptoms is

A)deficiency of an enzyme that enables T cells to stimulate B cells,providing immunity.
B)the stripping of the lipid layer from brain neurons.
C)proliferation of oligodendrocytes in the brain,causing a glioma tumor.
D)deficiency of an enzyme that is part of the urea cycle.

Question 42

The species naturally affected by Leber's congenital amaurosis II that led to development of gene therapy is

A)mice.
B)pea plants.
C)a breed of horse.
D)a breed of dog.