genetics final

Genetic tests offered to adults are for diseases that have a carrier frequency of at least ______.

1 in 100

Which of the following disorders does NOT involve faulty DNA repair?

Becker muscular dystrophy

Which of these genetic tests is done on children?

Both exome sequencing and genome sequencing

Identify the disease conditions that can be detected by a chromosomal microarray test.

Developmental delay Behavioral problems Intellectual disability Autism

Palindrome sequences are often found at mutation hotspots. Which of the following is a palindrome?

GATCGATC

Identify advantages offered by genetic testing to guide drug selection.

Monitoring response to drug treatment Predicting the course of the illness

Which of the following tests can detect variants of multiple genes or gene expression patterns that affect drug metabolism?

Pharmacogenomic

__________ can usually repair DNA damage caused by ultraviolet light.

Photoreactivation

Which are advantages associated with genetic screening of newborns?

Risks to future pregnancies can be determined. The newborn can undergo early treatment for a genetic disease.

Enzyme replacement therapy Substrate reduction therapy Pharmacological chaperone therapy

Supplies recombinant glucocerebrosidase Decreases the amounts of the substrate Stabilizes misfolded enzymes sufficiently to allow some function

The DNA sequence that is repeated many times in a telomere is

TTAGGG

Which are disadvantages associated with genetic screening of newborns?

The anxiety of parents while waiting for symptoms to appear can be increased. Anxiety and uncertainty can interfere with parent-child bonding.

Which of the following is a true statement about germline gene therapy?

The correction is heritable, passing to offspring.

Individuals with __________ develop numerous skin cancers when exposed to sunlight.

Xeroderma pigmentosum

Which of these has never been observed in a viable human birth?

YO male

One of the most commonly discussed "athletic" genes is alpha-______ 3 (ACTN3).

actinin

An initial success in gene therapy involved the addition of the gene for ______ to the white blood cells of patients with severe combined immune deficiency.

adenosine deaminase (ADA)

Gene therapy was first used to treat ______.

adenosine deaminase deficiency

Preimplantation genetic diagnosis, samples a cell from ______.

an early embryo

A mutation in a collagen gene is likely to affect the phenotype because

collagen has a very precise three-dimensional structure, so nearly any disruption alters the overall conformation.

Many pharmacogenetic tests detect specific variants of genes that encode enzymes called ___ that metabolize toxins, including by-products of normal metabolism as well as drugs.

cytochromes

Following a 1999 gene therapy treatment for X-linked severe combined immune deficiency, several patients developed ___ due to insertion of the retroviral vector converting a proto-oncogene into an active oncogene.

leukemia

Outcomes of nutrigenetics testing, as analyzed by the US Government Accountability Office, were indicative of ______ rather than ______.

lifestyle and diet information; DNA sequence analysis

For gene therapy, fatty structures called ____ are also used as vectors.

liposomes

For most genetic conditions, testing in newborns is carried out via an analytical chemistry technique called ______.

mass spectrometry

A germline mutation passes from generation to generation because it occurs during the DNA replication before

meiosis

Copy number variants

number in hundreds to thousands

A codon for which of the amino acids listed below has the most synonymous codons?

serine

A sign that mutation occurred in a person exposed to radiation in the aftermath of the Chernobyl disaster of 1986 was

short DNA repeats in a child's genome that didn't match the size in either exposed parent.

The first single-gene disorder for which the mechanism of mutation was understood at a molecular level was

sickle cell

Which of the following best describes adrenoleukodystrophy disease?

A mutation in the ABCD1 gene on the X chromosome prevents the portholes in the peroxisomes from admitting an enzyme needed to make myelin.

Identify the symptoms of type 1 Gaucher disease.

An enlarged liver and spleen, bone pain, and deficiencies of blood cells

______ is a technique that collects sperm and separates them into fractions that are enriched for X-bearing or Y-bearing cells, to increase the probability of having a girl or boy, respectively.

Flow cytometry

Which of the following includes a direct repeat within the sequence GTCCTTATTCA?

GTCCTTATATTCA

Which of the following is a true statement about flow cytometry?

It assigns each type of sperm a positive or negative charge.

Sanjay and Indira have thalassemia minor. Their young daughters are dizygotic (fraternal) twins. Malonie has thalassemia minor like her parents, but Jewel has the more severe thalassemia major. The more serious case most likely arose because

Jewel inherited two recessive mutant alleles in the beta globin gene that cause thalassemia.

Which of the following are genetic testing techniques used later in pregnancy?

Maternal serum markers Chorionic villus sampling Noninvasive prenatal testing Amniocentesis

What are the properties possessed by different viral vectors used for gene therapy?

May enter enough cells to alleviate symptoms or slow or halt progression of the disease May be able to carry a large piece of DNA

The chromosome test rescue karyotyping gives researchers evidence from past miscarriages that provides clues about future pregnancies. For example ______ can indicate ______ risk for future pregnancies.

translocations or inversions; increased

Which of the following is a true statement about somatic gene therapy?

A recipient does not pass the genetic correction to offspring.

Patients who were not satisfied with their response to an anti-depressant medication were found to have variants for which of the following genes?

CYP2C19 for P450 cytochrome

A "pharmacogenetic algorithm" considers two genes: two variants of _____ and one variant of VKORC1 that are associated with increased sensitivity to warfarin.

CYP2C9

Identify the genetic tests performed on children.

Genome sequencing Exome sequencing Chromosome tests Single-gene tests

_____ alters the DNA of a gamete or fertilized ovum, so that all cells of the individual have the change.

Germline gene therapy

Identify the viral vector used in the gene therapy for adrenoleukodystrophy.

HIV

Mutational hot spots occur most often where the DNA is

repetitive or symmetrical.

Flow cytometry is a technique that has been used to ______.

separate X-bearing sperm from Y-bearing sperm

Why is genetic testing used in the military?

To detect a disease that might put a soldier at risk To identify remains To diagnose a communicable disease on the battlefield

The fact that myotonic dystrophy worsens with each generation is due to

an increasing number of repeated short DNA sequences.

One of the genes that has gotten the most attention in predicting athletic ability is the ______-1-converting enzyme gene (ACE).

angiotensin

Patients with variations in the CYP2C19 gene for P450 cytochrome metabolized a(n) ______ drug more rapidly or more slowly than people who responded favorably to the drug.

anti-depressant

The type of DNA repair that corrects errors due to oxidative damage by replacing one to five nucleotides is

base excision repair.

The gene therapy for adrenoleukodystrophy fixes ______ cells outside the body, and introduces them into the bloodstream, where they go to the brain.

bone marrow

Spindle fibers (microtubules) attach to a chromosome's __________ during mitosis.

centromere

Genetic tests can identify adult carriers of more than 1,000 recessive disorders. These diseases affect ______ and can be diagnosed ______.

children; prenatally

In the context of genetic testing of children, a _____ detects very small deletions and duplications.

chromosomal microarray test

The parents-to-be were shocked when an ultrasound scan done in the second trimester of the pregnancy showed a fetus with obviously broken leg bones and ribs. The doctor diagnosed osteogenesis imperfecta. This is caused by a mutation in a gene that encodes

collagen

The area of genetics that links traits, including illnesses, to chromosome variations is

cytogenetics.

Acridine dyes are mutagens that

disrupt the reading frame of the gene.

Genetic testing of newborns now involves ______.

dna testing

In the context of predictive tests, a disease-associated genotype indicates _____.

elevated risk

The 250-bp insertion (I) in the ACE gene has been found to be more common among ______.

endurance athletes

Gene therapy strategies vary in invasiveness. One approach involves removing cells from the body, altering them, and then infusing them into the bloodstream through a vein. This is called ___ ___ gene therapy

ex vivo

Using a technique called flow cytometry, sperm are labeled with _____.

fluorecent markers

For parents who would like to know the traits of a "hypothetical offspring", a computer algorithm can predict the results of meiosis in the ___ of each of the parents and how these might combine to produce a child with a particular combination of ___ , interpreted as traits.

gametes, genotypes

Which addition to a DNA sequence would not cause a frameshift mutation?

gct

The transfer of normal genes into cells to replace the activity of defective ones in order to correct genetic disorders is a procedure known as

gene therapy

Which method for treating a genetic disease adds a wild type allele without removing the mutant disease-causing allele?

gene therapy

A mutation that changes the third position in a CUU codon to a C would

have no effect on the protein.

Which of the following is an adult-onset disease?

huntington's disease

In ______, the vector must enter the appropriate cells and the human DNA be transcribed into mRNA and translated into protein.

in vivo gene therapy

Amniocentesis cannot be used to detect fetal

intelligence

Which type of mutation substitutes one amino acid for another?

missense

Following a 1999 gene therapy treatment for X-linked severe combined immune deficiency, several patients developed leukemia, due to insertion of the retroviral vector activating a(n) ______.

oncogene

In 1999, 18-year old Jesse Gelsinger died during a gene therapy experiment aimed at treating his ______ deficiency.

ornithine transcarbamylase

In ______, a person cannot make a liver enzyme required to adequately break down dietary proteins.

ornithine transcarbamylase deficiency

Adrenoleukodystrophy is a disease of ______.

peroxisomes

a ____ test detects a variant of a single gene that affects drug metabolism.

pharmacogenetic

The first genetic condition tested for in newborns was ______.

phenylketonuria

A source of gamma radiation is

plutonium and cesium isotopes.

During the first few days following conception, when the embryo consists of only a few cells, sampling one of them can reveal mutations, and then the rest of the embryo is placed in the uterus to continue development. This technique is called _____.

preimplantation genetic diagnosis

A drug that was ineffective in treating cancer has been repurposed to help children who have a form of ______, a condition where aging is accelerated.

progeria

Based on an analysis by the US Government Accountability Office, current practices for nutrigenetics testing ______.

provide advice that does not rely on DNA analysis

A nonfunctional gene near a similar but functional gene is called a(n)

pseudogene

A new application of testing chromosomes, called _____, is done on tissue samples that were stored when a woman's uterus was scraped following a miscarriage.

rescue karyotyping

Family exome sequencing uncovered a mutated gene that affects synapse formation that explained symptoms currently affecting a 2-year old child. The same analysis showed inheritance of a mutation for Marfan syndrome, for which the child had not yet developed symptoms. The discovery of possible Marfan syndrome is called a(n) ______ finding.

secondary

a ___ finding arises when a mutation is discovered that is unrelated to a patient's current symptoms. The mutation may predict the development of another condition in the person's lifetime.

secondary / incidental

Like children, adults take ___ ____tests as part of diagnostic workups but adults also take genetic tests to detect increased risk of developing certain types of ____

single gene ; cancers

______ corrects only the cells that an illness affects.

somatic gene therapy

Heterochromatic regions at the ends of chromosomes are

telomeres

In a form of early-onset Alzheimer disease caused by a mutation on chromosome 14, A is changed to T at the first position of codon 146, which substitutes leucine for methionine. This mutation is a __________ and is __________.

transversion; missense

Allelic disorders may result from mutations in different parts of the same gene.

true

Different disease phenotypes caused by mutations in the same gene are termed allelic disorders.

true

True or false: The goal of newborn screening is to identify infants who are at very high risk of developing certain inherited diseases that are "actionable".

true

In _____, the enzyme glucocerebrosidase is deficient or absent.

type 1 Gaucher disease

In gene therapy, the working copies of genes are typically delivered to specific cell types via ______.

viruses

One of the first drugs to be described using pharmacogenetics was the blood thinner _____.

warfarin

Ashanthi DeSilva was one of the first children treated for ADA deficiency when functional ADA genes were introduced into her ___ ____ cells

white blood