Deck 20: Genetic Testing and Treatment

Question 1

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.

Answer 1

C

Question 2

Newborn screening reveals that newborn Jessica has inherited 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) twice daily respiratory therapy, performed by the parents.
E) dietary.

Answer 2

E

Question 3

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

A) adopt a child.
B) avoid one parent's passing on a disease-causing allele to a child.
C) learn if their fetus has an inherited disease.
D) avoid cancer in their children.
E) have a child who will excel at a particular sport or have a particular talent.

Answer 3

B

Question 4

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

A) Accutane, an acne drug.
B) an early pregnancy test kit.
C) Viagra, a drug to treat erectile dysfunction.
D) Warfarin, a blood thinner.
E) a narcotic to treat chronic pain.

Question 5

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.
E) explain that Sheree is obviously a new mutation and that the likelihood that her husband is too is very low, so there is no concern that the child would be affected.

Question 6

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) results from tests for traits and talents done with a direct-to-consumer genetic testing company using risk figures from genome-wide association studies.
D) the family health history, extending to second degree relatives.
E) a list of the occupations of every family member.

Question 7

Nondirective genetic counseling

A) does not accept health insurance.
B) does not deal with disorders carried on the sex chromosomes.
C) is provided by a counselor who is the same gender as the patient.
D) considers diseases caused by genes that are located throughout the genome.
E) offers options but not opinions.

Question 8

The phrase "When you hear hoofbeats,think horses,not zebras" applies to genetics in that

A) horse breeders need to know genetics to select which horses to cross.
B) transgenic zebras may have horse genes.
C) transgenic horses may have zebra genes.
D) syndromes with seemingly unrelated symptoms are often inherited.
E) inherited diseases are very rare compared to other types of diseases.

Question 9

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
E) take a DNA sample, extract and amplify the DNA, perform specific tests on the genome or sequence all of it, and explain the results to the patient

Question 10

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

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.
E) occurs after the person has taken the test for the mutation.

Question 11

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) pharmacophenetics.
C) pharmacogenomics.
D) pharmacology.
E) recombinant DNA technology.

Question 12

Newborn screening using tandem 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.
E) genome sequences.

Question 13

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 screen.
C) genome screen.
D) predisposition test.
E) genome-wide association study.

Question 14

Nonheritable gene therapy is performed on _______ cells.

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

Question 15

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) provides a drug that accompanies a specific mutation, correcting it.
E) replaces a missing enzyme.

Question 16

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

A) the disease is non penetrant.
B) genetic tests are untrustworthy.
C) the disease is genetically heterogeneic.
D) the disease is not inherited.
E) the genotype changes as a person ages, especially in women.

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

The field of genetic counseling began when the term was coined

A) in 1986, when the human genome project was first suggested.
B) in 2001, when the first draft of the human genome was published.
C) in 1947, to help physicians explain inherited diseases to their patients.
D) in 1953, when Watson and Crick discovered the structure of DNA.
E) in 1865, when Gregor Mendel published his work on inheritance patterns in pea plants.

Question 19

Rita has been diagnosed with Her2 breast cancer,and is prescribed Herceptin.The approach of basing a drug prescribing decision on the results of a single-gene test is called

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

Question 20

Enzyme replacement therapy treats

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

Question 21

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) Ebola virus
E)E. coli

Question 22

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.
E) excess of a clotting factor.

Question 23

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

A) injecting PEG-ADA purified from a cow
B) injecting white blood cells genetically modified to carry functional ADA genes
C) supplying progenitor T cells genetically modified to carry functional ADA genes shortly after birth
D) using siRNA to knockdown ADA genes
E) . using cDNA to produce ADA in E. coli

Question 24

Muscle is a good target for gene therapy because

A) it is an abundant tissue with a rich blood supply.
B) muscular dystrophy is an autosomal dominant trait.
C) genes that function in muscles tend to be small.
D) muscle cells can be stimulated to divide with exercise.
E) the musculature is similar in males and females.

Question 25

A difficulty in developing gene therapy for diseases of the nervous system is that

A) neurons are located throughout the body.
B) correcting a defect in a neuron anywhere in the body would also affect the brain, in unpredictable ways.
C) nerve cells (neurons) do not divide, and so the change would not be perpetuated.
D) the nervous system has many functions.
E) nervous tissues comprise half of the body's mass.

Question 26

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 cannot infect rapidly dividing cells.
D) it causes ADA accumulation.
E) reverse transcriptase will not work in human cells.

Question 27

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) constitutional gene therapy.
D) somatic gene therapy.
E) in vitro fertilization.

Question 28

Germline gene therapy would correct a genetic defect in

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

Question 29

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
E) he had a conditional mutation

Question 30

A patient received bone marrow modified by an adeno-associated virus (AAV)carrying the 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.
E) IVF.

Question 31

A retrovirus is given a functional version of a gene that a patient lacks and used to infect the patient's skin cells growing in culture.Skin is grown from the altered cells and grafted onto the patient.If all works well,the graft will

A) be viewed as immunologically foreign and destroyed.
B) be accepted and secrete the inserted gene's protein product.
C) turn on the abnormal gene in surrounding cells.
D) be accepted, but not express the introduced gene.
E) shrivel and undergo apoptosis.

Question 32

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.
E) in vitro fertilization.

Question 33

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
E) receiving cord blood stem cells from a donor

Question 34

Adenosine deaminase (ADA)deficiency results in

A) Canavan disease.
B) hereditary emphysema.
C) neurotransmitter imbalances.
D) severe combined immune deficiency.
E) chronic myelogenous leukemia.

Question 35

Performing gene therapy on somatic cells removed from the body and then returned to the body is called _______ gene therapy.

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

Question 36

Gene therapy to treat muscular dystrophy targets the gene that encodes

A) actin.
B) dystrophin.
C) collagen.
D) myoglobin.
E) myosin.

Question 37

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
E) a clotting factor

Question 38

Introducing a gene in a liposome through holes bored into the skull is a(n)_______ gene therapy.

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

Question 39

An effective vector to genetically alter respiratory cells might be

A) a Ti plasmid.
B) adenovirus.
C) a herpes simplex virus.
D) HIV.
E) human papilloma virus.

Question 40

The liver is a good candidate for gene therapy because

A) it has only one function.
B) it is large.
C) it is both an organ and a gland.
D) only part of it need be corrected.
E) we know all of the genes that can affect it when mutant.

Question 41

Gene therapy for Leber's congenital amaurosis II consists of

A) replacing an enzyme that restores the function of T and B cells.
B) injecting wild type alleles of the RPE64 gene into affected cells of the retina.
C) injecting wild type alleles of the dystrophin gene into affected muscle cells.
D) inhaling viruses that have been modified to carry the wild type CFTR gene.
E) injecting the gene encoding ornithine transcarbamylase into a vein in the liver.

Question 42

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

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