GM 03: Testing Flashcards
Genetic tests often performed on (X) material that’s purified from patient’s (Y) samples.
X = DNA Y = blood
T/F: Only blood samples can be used for genetic tests.
False - some cases require other tissues to be examined
Abnormal events during (X) can cause disruption of normal (Y). These are gross structural/numerical changes that are detected with techniques that (Z).
X = meiosis; Y = chromosome number and structure; Z = image whole chromosomes
List techniques that detect abnormalities in whole chromosome number/structure.
- Karyotype (and spectral karyotyping (SKY))
- (Interphase) FISH
- Chromosomal microarray
Karyotype allows visualization of (X), stained with (Y).
X = metaphase chromosomes Y = Giemsa dye
(X) imaging technique paints each chromosome a different color. (Y) probes are used to target (Z).
X = Spectral Karyotyping (SKY) Y = DNA Z = specific chromosomes
In SKY, you would expect to see (X) number of each colored (Y) in a diploid sample.
X = 2 Y = chromosome
Name one key benefit to using SKY. Which abnormality is visually obvious?
Contrasting colors make presence of translocation obvious
(X) chromosomal test(s) require both harvesting and amplification of patient’s cells.
X = karyotyping
T/F: Interphase FISH technique requires neither harvesting nor amplification of patient cells.
False
List the main characteristics that can be visualized/identified in karyotyping.
- Number
- Size/structure
- centromere position
- Banding pattern
To avoid the need to harvest and amplify patient cells for chromosomal testing, which method(s) can be used?
- (Interphase) FISH
2. Chromosomal microarray
Interphase FISH uses probes directed toward:
Particular chromosomal region
Interaphse FISH technique primarily used to ID changes in:
Chromosomal copy number
How can Interphase FISH be used to ID a translocation?
Two probes from different chromosomes are found to co-localize
T/F: Interphase FISH test results should always be verified with full karyotyping.
True
Key disadvantage of microarray.
Only able to pinpoint changes in copy number, not spatial organization
Microarray can’t detect (X) rearrangement/translocation due to its inability to detect (spatial/numerical) changes in chromosomes.
X = balanced;
Spatial
PCR and (X) blotting techniques are primarily used to detect changes in (Y) of (Z).
X = Southern; Y = size Z = genes
T/F: Generally, PCR will not detect subtle change in DNA sequence.
True
How can a PCR-based approach, aka (X) approach, be modified to identify specific changes to gene sequence?
X = allele-specific PCR
The expected mutation is known
How would you design the PCR (X) in allele-specific PCR to detect subtle change?
X = primers;
Complementary to either wild-type or mutant allele sequence
In allele-specific PCR, what tells you the patient has mutant (X)?
X = allele;
If you use primer complementary to mutant allele and the target amplification proceeds
Aside from allele-specific PCR, a similar method is allele-specific (X). This method uses which part of genetic information?
X = hybridization;
Full genomic DNA
Allele-specific hybridization. (X) is hybridized to (Y). Which tool is used to then detect (Z)?
X = complete genomic DNA;
Y = spot on nylon membrane
Labeled oligoNT probe
Z = either normal or mutant allele
T/F: Allele-specific hybridization allows you to skip electrophoresis step of allele-specific PCR.
True
T/F: DNA separated by size in allele-specific hybridization.
False
How could disease exhibiting allelic heterogeneity be detected via allele-specific PCR/hybridization?
Can’t - a more unbiased approach needs to be implemented