Deck 17: Applications of Recombinant DNA Technology

Question 1

When yeast cells are cultured in the presence of both glucose and galactose, the GAL genes are

A) transcribed and translated.
B) neither transcribed nor translated.
C) transcribed but not translated.
D) translated but not transcribed.
E) none of the above.

Answer 1

B

Question 2

Chromosome walking involves

A) cloning a gene in stepwise fashion using partially overlapping subclones.
B) use of PCR to generate fragments of chromosomes.
C) constructing a cDNA library.
D) G-Staining and labeling the banding series of each chromosome.
E) none of the above.

Answer 2

A

Question 3

ASO probes are used for the molecular testing of

A) defective proteins implicated in disease.
B) RFLP fragments in a DNA region.
C) single-nucleotide changes in a DNA region.
D) successfully cloned Ti plasmids.
E) chromosomal rearrangements.

Answer 3

C

Question 4

Prenatal genetic tests cannot determine

A) the gender of a fetus.
B) if a fetus has a specific mutation.
C) the DNA fingerprint for certain VNTR loci in a fetus.
D) if chromosomal abnormalities exist in a fetus.
E) All of these can be determined.

Question 5

The Human Genome Project was launched in ________, and the complete working draft was announced in ________.

A) 1997, 2001
B) 1953, 1985
C) 1990, 2001
D) 1953, 2001
E) 1990, 1997

Question 6

Variable-number tandem repeats can differ in

A) length of repeat motif.
B) number of units repeating in tandem.
C) base sequence in repeat motif.
D) A and C
E) A, B, and C

Question 7

The first gene to be cloned using only positional cloning was for which disease?

A) Muscular dystrophy
B) Huntington disease
C) Cystic fibrosis
D) Tay-Sachs disease
E) Sickle-cell disease

Question 8

Successful cotransformation in the yeast two-hybrid system will result in the binding of proteins produced by each yeast expression vector. These fusion proteins function by

A) binding to the lacZ operator, preventing transcription.
B) binding to the lacZ repressor, enabling transcription.
C) changing color in the presence of X-gal.
D) binding to RNA polymerase, preventing transcription.
E) binding to the lacZ upstream activator sequence, enabling transcription.

Question 9

Ti plasmids are approximately ________ the related pUC19 plasmids.

A) 100 times larger than
B) 10 times larger than
C) 10 times smaller than
D) half the size of
E) twice as large as

Question 10

Allelic variants differing by a single nucleotide are called

A) monoallelic polymorphisms (MAPs).
B) monomorphic alleles (MMAs).
C) uninucleotidic variants (UNVs).
D) single-nucleotide polymorphisms (SNPs).
E) none of the above.

Question 11

In a DNA fingerprinting-based paternity analysis, the tested child should share about ________ of the fingerprint bands with his or her father.

A) 1/8
B) 1/2
C) 1/16
D) 1/4
E) All of the above

Question 12

Polymorphic tandem repeats are called

A) STRs.
B) VNTRs.
C) PTRs.
D) A and B
E) A, B, and C

Question 13

Genetic testing is generally done for

A) newborn screening.
B) carrier (heterozygote) detection.
C) prenatal diagnosis.
D) all of these reasons.
E) B and C only

Question 14

Genetic tests primarily tell investigators

A) if there is a mutation known to be associated with a disease.
B) if an individual is likely to express disease alleles.
C) how to cure a genetic disease.
D) the genetic cause(s) of a disease.
E) all of the above.

Question 15

To study how protein interactions affect cellular function, ________ is the most appropriate method.

A) RT-PCR
B) Southern blotting
C) the two-hybrid system
D) PCR
E) restriction mapping

Question 16

To locate the CF gene, people in the pedigree were screened with ________ to detect any genetic markers associated with the disease.

A) ASOs
B) RFLPs
C) antibodies
D) PCR
E) all of the above

Question 17

Approximately what percentage of the human genome consists of repetitive DNA?

A) 50 percent
B) 85 percent
C) 25 percent
D) 97 percent
E) 3 percent

Question 18

In order for the yeast galactose metabolizing gene, GAL1, to be transcribed, the regulatory protein produced by the GAL4 gene binds to

A) the operator sequence.
B) the repressor protein.
C) upstream activator sequence G (UASG) region.
D) RNA polymerase.
E) a ribosome.

Question 19

If β-globin DNA from a normal individual is cut with the restriction enzyme DdeI, transferred to a membrane, and probed with a labeled β-globin probe, ________ restriction fragments would be detected.

A) six
B) two
C) three
D) four
E) five

Question 20

In yeast, expression of galactose utilization genes is induced when there is ________ in the culture medium.

A) lactose
B) glucose
C) maltose
D) galactose
E) Any of the above

Question 21

A couple with STR genotypes (50, 75) and (50, 100) (where the allele numbers denote repeat length) have several children. What are the possible genotypes of their children for this STR locus?

Question 22

How do genetic tests differ from diagnostic tests for genetic disease?

Question 23

Briefly describe some of the applications of DNA fingerprinting in (1) criminal justice, (2) enforcing game laws, (3) studying ancient organisms, and (4) conservation genetics.

Question 24

Study of the fruitless (fru) gene in Drosophila has shown that gene regulation can be accomplished by differential mRNA transcript processing. Explain.

Question 25

Briefly explain how Ti plasmids induce crown gall (tumor) growth in plants parasitized by A. tumefaciens, highlighting the specific properties that make this plasmid so useful in biotechnology.

Question 26

Briefly list the basic steps involved in constructing a DNA fingerprint for a paternity case.

Question 27

DNA-level screening for genetic disease typically involves RFLP- or PCR-based approaches.

Question 28

Much plant genetic engineering is accomplished with the soil bacterium Agrobacter tumefaciens.

Question 29

A DNA polymorphism is defined as two or more alternative forms or alleles differing in sequence at a specific chromosomal locus.

Question 30

Somatic cell gene therapy can result in a cure for a genetic disease in an individual as well as any progeny produced by the individual.

Question 31

The Guthrie test is used to screen all newborns in the United States for cystic fibrosis.

Question 32

Sickle-cell disease and one form of open-angle glaucoma are genetic diseases known to stem from a single amino acid change.

Question 33

Two STR loci were determined to have the following allele frequencies in the general population: STR A STR B Alleles: 1A: 0.1 1B: 0.4 2A: 0.55 2B: 0.4 3A: 0.25 3B: 0.2 4A: 0.1 A suspect in a criminal trial was genetically tested for these loci and was found to have the genotype (1A, 1A) for STR A and (2B, 2B) for STR B-homozygous for both loci. What is the probability that a randomly sampled person from this population would also have this genotype?

Question 34

Antisense mRNA can be used to regulate the expression of genes. Briefly describe how this technology was used to slow the ripening of Calgene's ill-fated Flavr-SavrTM tomato.

Question 35

Ti plasmids and the T-DNA system can be used to transform any vascular plant.

Question 36

Genetic testing is typically done with blood samples, yet red blood cells (erythrocytes) are anucleate (lack nuclei) and are thus devoid of DNA. How, then, are these tests done?

Question 37

DNA fingerprinting can be used to convict criminals but has little application in exonerating individuals already convicted.

Question 38

Prior to the successful and cloning and industrial-scale manufacture, substances like blood clotting factor VIII (used to treat hemophilia) had to be collected from people. What dangers inherent in this are avoided by engineering a recombinant molecule?

Question 39

The gene responsible for cystic fibrosis was identified by positional cloning, the first such genetic disease identified in this way.

Question 40

What are some ethical concerns over germ-line gene therapy?

Question 41

Monsanto Corporation developed transgenic crop plants conferring tolerance of the herbicide RoundupTM (glyphosate), which Monsanto owns. What are some pros and cons, in ecological and economic terms, of producing such herbicide-resistant plants?

Question 42

The ready availability of genetic tests for a diversity of genetic diseases has raised concerns among some physicians and bioethicists. What do you think some of those concerns are? What problems can arise from this technology?

Question 43

Rapid detection of SNPs, which are allelic variants, can be accomplished with DNA microarrays. If a microarray is set up for a set of genes, including all variants, outline a general procedure for quickly assaying the genotype of multiple individuals for that set of genes.

Question 44

Considerable concern has been voiced over engineering crop plants with certain kinds of traits, notably the expression of pesticide genes and herbicide resistance, for fear that such traits may find their way into natural plant populations, including weeds. How might this be prevented?