Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2nd Year 2nd Term > MT6315 LESSON 8 FISH & CGH > Flashcards

MT6315 LESSON 8 FISH & CGH Flashcards

1
Q

FISH stands for?

A

Fluorescence In situ Hybridization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

FISH is a cryogenic technique that uses what to do what?

A

Fluorescent probes to bind specifically to a part of chromosomes complementary to its sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The fluorescent probes use what kind of light?

A

Excitation light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Small strips of single stranded DNA complementary to the sites being examined

A

Probes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many bases are usually seen in the probes?

A

~200-400

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

FISH is useful in detecting and mapping what?

A

The presence or absence of particular DNA sequences within chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the DNA bound to the probe called?

A

Target DNA or native DNA from the patient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Probes are (artificial/native)

A

Artificial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

FISH is applied to provide what?

A

specific localization of genes on chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is acquired using specific probes?

A

Rapid diagnosis of trisomies and microdeletions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

FISH is also used to check the cause of?

A

trisomies, microdeletion syndromes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

(Native/Artificial DNA) is on the slide prep to allow for visualization

A

Native

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

T or F: Karyotyping and PCR are more cost-effective than FISH technique in detecting disease

A

F, FISH is more cost-effective since culturing is no longer needed thus lowering costs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Sequencing by FISH can be performed in what condition of the DNA?

A

Preserved/ Undegraded Metaphase DNA (should being intact)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What binds to the target DNA?

A

Fluorescently labelled probe DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Target DNA is also called t______

A

template

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Process of separating the DNA strands and to allow the probe to access target DNA

A

Denaturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How is denaturation usually done?

A

Heat or chemical means via Formamide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is denatured, native or artificial DNA?

A

Native/ Target

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

T or F: FISH is possible in interphase chromosomes

A

T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Process of binding together the probe to the target DNA

A

Hybridize/ Hybridization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Probe signals are analyzed using?

A

A fluorescent microscope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the 2 specimen types for FISH?

A

Metaphase FISH
Interphase FISH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

METAPHASE OR INTERPHASE FISH: Gold standard and routinely done

A

Metaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

METAPHASE OR INTERPHASE FISH: Done on cultured cells

A

Metaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

METAPHASE OR INTERPHASE FISH: Allows direct visualization of chromosomes and exact position of signals

A

Metaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

METAPHASE OR INTERPHASE FISH: Useful in the detection of structural changes in the genome

A

Metaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

METAPHASE OR INTERPHASE FISH: Can be modified to be used in de novo mutations

A

Metaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

METAPHASE OR INTERPHASE FISH: May also be done on uncultured specimens

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

METAPHASE OR INTERPHASE FISH: Advantageous in the rapid screening of many nuclei for prenatal diagnosis and newborn studies

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

METAPHASE OR INTERPHASE FISH: Beneficial in the study of samples with a low mitotic index such as most solid tumors

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

METAPHASE OR INTERPHASE FISH: Major disadvantage is the inability to detect unknown structural chromosomal changes.

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

METAPHASE OR INTERPHASE FISH: Probe is already made with the disease in mind

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

METAPHASE OR INTERPHASE FISH: Whole chromosome is of interest

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

METAPHASE OR INTERPHASE FISH: Not suitable for de novo mutation

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

METAPHASE OR INTERPHASE FISH: Offers opportunity for same day turn around time

A

Interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

METAPHASE OR INTERPHASE FISH: May be used in karyotyping to visualize the exact position of the fusion

A

Metaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Why is metaphase FISH the gold standard?

A

More rigorous and the best time to see the components of the chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Considered a “pre-test” for duplications, deletions

A

CGH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Samples that can be used for Metaphase FISH

A
  1. Amniocytes
  2. Chorionic villous cells
  3. Lymphocytes
  4. Cells from bone marrow aspirates or solid tumors
  5. Fibroblasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Samples that can be used for Interphase FISH

A

Amniocytes – for ploidy analysis during prenatal studies

Peripheral blood smears – for ploidy analysis in newborns

Bone marrow aspirate smear or direct harvest – translocation or copy number analysis in cancer studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Complementary sequences of target nucleic acids (DNA, RNA or nucleic acid analogs) tagged or labeled with fluorophores

A

FISH Probes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the size range for the FISH probes?

A

20-1000 base pairs (1000 base pairs = 1 megabase)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

2 types of labelling in FISH probes?

A

Direct and Indirect Labelling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

DIRECT OR INDIRECT LABELLING: Fluorophores are directly attached to the probe

A

Direct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

DIRECT OR INDIRECT LABELLING: Drawback is that is it less sensitive

A

Direct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

DIRECT OR INDIRECT LABELLING: FITC, Rhodamine

A

Direct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

DIRECT OR INDIRECT LABELLING: Cyanines

A

Direct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

DIRECT OR INDIRECT LABELLING: Fluorophores usually attached at the end of the DNA

A

Direct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

DIRECT OR INDIRECT LABELLING: Chemical conjugation of the nucleic acid with a nonfluorescent molecule that can bind fluorescent material after hybridization

A

Indirect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

DIRECT OR INDIRECT LABELLING: Biotin and Digoxigenin

A

Indirect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Unbound fluorescent dyes are also known as?

A

Background dyes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Biotin is derived from?

A

Egg yolk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Biotin’s partner molecule is usually?

A

Avidin which has the fluorescent dye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Have very strong covalent action in nature

A

Biotin and Avidin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Which is attached to the dye, avidin or biotin?

A

Avidin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Which is attached to the probe, avidin or biotin?

A

Biotin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What are the different types of FISH probes?

A

Locus Specific Probe
Alphoid or Centromeric repeat probe
Subtelomeric Probe
Whole Chromosome Probe
Pre-natal FISH Probe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

WHAT KIND OF FISH PROBE: Binds to a particular region of a chromosome

A

Locus specific

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Locus specific probe is only used when?

A

only a small portion of a gene is isolated;

to determine on which chromosome the gene is located, or how many copies of a gene exist within a particular genome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Locus specific identifiers are more ____ specific

A

Gene/region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

The locus specific probes span the specific region and average what range of kb in size?

A

200-300 kb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Locus specific identifies are useful diagnostic tools to detect?

A

Deletions
Duplications
Rearrangements
Amplifications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Locus specific identifies can also be used in?

A

Fusion-type probe strategies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

2 types of Color FISH probes in Locus-specific probes?

A

Single color
Dual color

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

SINGLE OR DUAL COLOR FISH PROBE: Designed to cover a gene of interest

A

Single

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

SINGLE OR DUAL COLOR FISH PROBE: Designed to cover any 2 genes for the detection of any aberrations.

A

Dual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Dual color FISH probe allows simultaneous detection of?

A

numerical abnormalities of two to three regions in one FISH assay.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

SINGLE OR DUAL COLOR FISH PROBE: Creates a color that is a mixture of the previous colors which signifies a gene fusion

A

Dual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Dual fusion FISH strategies are probes that span what?

A

Specific regions of interest with recurring breakpoints

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Dual fusion FISH strategies are used to identify what?

A

Chromosome rearrangements involving 2 chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

WHAT KIND OF FISH PROBE: Generated from repetitive sequences found in the middle of each chromosome

A

ALPHOID/CENTROMERIC REPEAT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

WHAT KIND OF FISH PROBE: Used to determine whether an individual has the correct number of chromosomes or if there is aneuploidy in the patient’s genome

A

ALPHOID/CENTROMERIC REPEAT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Alpha-satellite probes are also known as?

A

Chromosome Enumeration probes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Alpha-satellite probes bind to?

A

Highly repetitive DNA

76
Q

Alpha-satellite probes are most often used as what kind of probes?

A

Control probes

77
Q

Most alpha-satellite probes give out what to detect aneuploidies?

A

Large, bright signal

78
Q

WHAT KIND OF FISH PROBE: Specific to the subtelomere region of chromosome

A

Subtelomere Probe

79
Q

WHAT KIND OF FISH PROBE: Useful in the detection of subtelomere deletions and
rearrangements

A

Subtelomere Probe

80
Q

A kind of deletion that is important in cancer detection

A

Subtelomere deletions

81
Q

WHAT KIND OF FISH PROBE: Collection of smaller probes that bind to the whole length of chromosome

A

Whole Chromosome Probes

82
Q

Whole Chromosome Probes are useful in the examination of?

A

chromosomal aberrations

83
Q

Hybridize to the unique sequences which cover the length of an entire chromosome or chromosome arm

A

Whole chromosome paints

84
Q

Whole chromosome paints are useful in studying what?

A

Marker chromosomes, translocations and aneuploidy in metaphase cells

85
Q

Are whole chromosome paints useful in Interphase cells?

A

No

86
Q

T or F: Whole chromosome paints are useful in detecting insertions

A

T

87
Q

WHAT KIND OF FISH PROBE: Comprise of different combinations of fluorophore- labeled probes

A

Pre-Natal FISH Probes

88
Q

Pre-Natal FISH Probes are specific for what chromosomes?

A

chromosomes 13, 18, 21, X, and/or Y

89
Q

T or F: Pre-Natal FISH Probes provide a shorter TAT than karyotyping

A

T

90
Q

Steps in FISH?

A
  1. Probe and target DNAs are denatured using high temperature incubation in a formamide/ salt solution.
  2. Probe sequences hybridize to the complementary target sequences, and nonspecific binding is eliminated via stringent washing.
  3. The probe hybridization is detected with fluorescence microscopy
91
Q

What are some applications of FISH?

A
  1. Detection and characterization of chromosome abnormalities
  2. Detection and analysis of prenatal chromosomal abnormalities
  3. Study of chromosomal abnormalities associated with cancer
92
Q

a technique that uses DNA from the cells of interest, rather than using a standard karyotype, for chromosomal analysis.

A

Comparative Genomic Hybridization (CGH) on Metaphase Cells

93
Q

This can be very useful, especially in some cancers when only DNA is available rather than any growing cells.

A

Comparative Genomic Hybridization (CGH) on Metaphase Cells

94
Q

This technology has been used successfully for clinical analysis, particularly with cases that have a low (or no) mitotic index.

A

Comparative Genomic Hybridization (CGH) on Metaphase Cells

95
Q

CGH is NOT useful for detecting what?

A

balanced rearrangements

96
Q

A technique that allows the investigator to view a karyotype so that each chromosome is “painted” with a different color

A

Multiplex FISH (M-FISH)

97
Q

Used to create a distinct computer-generated false color for each chromosome

A

Ratio-labeled probes

98
Q

Useful for complex rearrangements, such as those seen in neoplastic disorders and solid tumors

A

Multiplex FISH (M-FISH)

99
Q

Uses chromosome-specific mixtures of partial chromosome paints that are labeled with various fluorochromes

A

Muticolor Banding (mBAND) analysis

100
Q

In mBAND, a computer program analyzes metaphase chromosome data and produces what?

A

pseudocolored, banded karyotype with an estimated resolution of 550 bands, regardless of chromosome length

101
Q

Advantageous for the determination of breakpoints and the analysis of intrachromosomal rearrangements and can be particularly useful in preparations with shorter chromosomes.

A

Muticolor Banding (mBAND) analysis

102
Q

A technique that is almost entirely used for research

A

Fiber Fish

103
Q

It allows the chromosomes to be stretched out and elongated

A

Fiber Fish

104
Q

The probes are applied and can be physically ordered on the fibers

A

Fiber Fish

105
Q

Provides a much higher spatial resolution and allows for correct orientation and placement of probes and for precise mapping of probes

A

Fiber Fish

106
Q

Essentially PCR on a slide

A

Primed In Situ Labeling (PRINS)

107
Q

In PRINS, primers of interest are ________ on a slide and then subjected to cycles of __________ that are used to incorporate labeled nucleotides. The labels are then detected _________, or labeled nucleotides are _________________ during the reaction

A

hybridized
denaturation, reannealing, and elongation
fluorescently
incorporated

108
Q

PRINS can differentiate hybridization with the alpha satellite sequences for chromosomes _____ and _____ , something that cannot be done with traditional FISH

A

13 and 21

109
Q

Used to identify material of unknown origin

A

Reverse FISH

110
Q

In reverse FISH, unidentified material, such as a marker chromosome or duplication, is ____________ off of a slide after ___________

A

flow sorted or microdissected
G-banding

111
Q

The DNA from this material is extracted, PCR- amplified and labeled with a fluorochrome. This is then used as a probe and hybridized to normal or patient metaphase chromosomes to identify the origin of the unknown material

A

Reverse FISH

112
Q

Template is the one with the probe, not the nature DNA

A

Reverse FISH

113
Q

Dividing specimen for FISH testing

A

Metaphase cells

114
Q

Non-dividing specimen for FISH testing

A

Interphase cells

115
Q

Direct preparation samples from interphase cells include?

A

Uncultured cells from blood, bone marrow and cytospins

Smears made from blood, buccal cells, bone marrow

116
Q

Paraffin embedded tissue sections under interphase cells include?

A

Tumors
Products of conceptions

117
Q

What are FFPE preserved tissues?

A

Formalin Fixed Paraffin Embedded Tissues

118
Q

What step in the FISH process includes the treatments to harden chromatin and dehydration?

A

Specimen processing/ harvesting

119
Q

T or F: FISH specimen includes baking at high temperature similar to that of G banding

A

F, does NOT include baking

120
Q

What will happen if the sample for FISH was baked at high temperatures?

A

The chromatin will dry our and will result in poor or low hybridization process

121
Q

What temperature is the FISH process usually set at?

A

37C

122
Q

Denaturing of DNA includes breaking what?

A

Hydrogen bonds to form single stranded DNA

123
Q

The denaturation temperature is lowered using what?

A

Formamide

124
Q

Hybridization with fluorescently labelled DNA probes includes what process which lasts for several hours?

A

Reannealing

125
Q

Incubation period for reannealing is usually how long?

A

4-20hrs

126
Q

Temperature has to (lower/heighten) for reannealing

A

Lower

127
Q

What needs to be washed off after staining?

A

Excess unbound probe / background

128
Q

What happens if the excess bound probes are not washed off?

A

There will be noise and this is decrease the specificity of the process

129
Q

What solution is effective is removing the unbound DNA?

A

Stringent Solution

130
Q

What is used to visualize nuclear boundaries and the morphology?

A

Counterstain

131
Q

What are examples of counterstains to visualize nuclear boundaries and morphology?

A

Propidium iodide and DAPI

132
Q

In this probe strategy, the probes will flank the specific region of interest

A

Break apart (BAP) FISH probe strategy

133
Q

BAP strategy is used to detect what?

A

Chromosomal rearrangements where there are multiple known partners (promiscuous genes)

134
Q

BAP strategy is useful in what type of samples?

A

FFPE

135
Q

What are some clinical applications of FISH?

A

Additional interpretation of abnormal karyotypes

Detecting diagnostic abnormalities

Providing prognostic information in some cancer types

Abnormal FISH patterns may serve as a monitor of disease or response to therapy

136
Q

Alterations of the DNA of a genome that results in the cell having an abnormal number of copies of one or more section of the DNA

A

Copy Number Variations (CNVs)

137
Q

On certain chromosomes, CNVs result in the large regions of the chromosomes being _____ OR _______

A

Deleted (fewer than normal) or duplicated (more than normal)

138
Q

What can contribute to tumorigenesis?

A

Amplifications and deletions

139
Q

What is the most common change seen in malignancies?

A

Amplifications

140
Q

Provides an approach to associate an aberration with a disease phenotype and localizing critical genes

A

Detection and mapping

141
Q

Affected by localizing the biomarkers that would indicate the phenotype of the disease

A

Prognosis and therapeutics

142
Q

What are the other uses of CGH?

A

Resistance and susceptibility to disease
Mental retardation, developmental delay and seizures
Dysmorphic features and multiple congenital anomalies
Schizophrenia and autism

143
Q

Molecular cytogenetic method for the analysis of CNVs in the DNA content of a given subject’s DNA, often in tumor cells

A

Comparative Genomic Hybridization or Chromosomal Microarray Analysis (CMA)

144
Q

CGH/CMA was first described by?

A

Kallioniemi et al 1993

145
Q

What are the 2 types of techniques in CGH?

A

Chromosomal technique
Genomic technique

146
Q

In CGH, how are metaphase chromosomes made into single stranded?

A

Alkaline treatment done on the disease and normal chromosome (should be from the same person)

147
Q

In CGH, the DNA from the subject tissue and normal tissue are labelled with?

A

Different tags

148
Q

For array or matrix CGH, the DNA is _______ to _______ chromosomes

A

Hybridized
Metaphase

149
Q

What can be detected and used for identifying abnormal regions in the genome?

A

Regional differences in the fluorescence ratio of gains and losses vs control DNA

150
Q

What is applied for detecting all genomic imbalances?

A

CGH (special FISH technique using dual probes)

151
Q

The basics of the CGH technique comprises what?

A

The comparison of total genomic DNA of the given sample DNA with total genomic DNA of normal cells

152
Q

T or F: Identical amount of both tumor and normal DNAs are labelled with the same fluorescent dyes in CGH

A

F, labelled with 2 different fluorescent dyes

153
Q

The mixture of the tumor and normal DNAs in CGH is added and hybridized to a?

A

Lymphocyte metaphase slide

154
Q

What devices/equipments are used for evaluation in CGH?

A

Fluorescent microscope equipped with a CCD camera

155
Q

What is a CCD device?

A

Charged couple device - a capture device that can count and interpret signals

156
Q

CGH is used to determine what?

A

copy number alterations of genome in cancer and those cells whose karyotype is hard or impossible to prepare or analyze

157
Q

T or F: CGH will detect only unbalanced chromosomal changes

A

T

158
Q

T or F: CGH can detect structural chromosome aberrations such as balanced reciprocal translocations or inversions

A

F, CANNOT be detected, as they do not change the copy number.

159
Q

CGH is _____________ of two differentially labeled genomic DNAs (eg. tumor and normal) to human metaphase chromosome spreads.

A

based onco-hybridization

160
Q

CGH is based on the ____________ onto ____________, which usually have been prepared from ____________ of a healthy donor.

A

co-hybridization of differentially labelled test and reference DNA
metaphase spreads
peripheral blood lymphocytes

161
Q

In the CGH process, the __________ of the two labels along the chromosomes then reflect _____________ in the test genome relative to the _____________.

A

signal intensity ratios
DNA copy number changes
reference genome

162
Q

The resolution for the signal intensity ratio of the 2 labels for CGH is limited to about?

A

3-10Mb

163
Q

In CGH, after extraction of test DNA (i.e. from a tumor sample) and normal DNA (i.e. from peripheral blood), the samples are differentially labeled with?

A

discernable fluorochromes

164
Q

What are examples of discernable fluorochromes used for labelling test and normal DNA?

A

tumor DNA with FITC [green] and control DNA with TRITC [red]

165
Q

In CGH, the genomes are combined with an excess of what and hybridized to?

A

Cot 1 DNA and hybridized to metaphase chromosomes

166
Q

What is a common problem in assays?

A

Background hybridization due to repetitive DNA sequences

167
Q

What blocks repetitive DNA sequences and prevents non specific hybridization?

A

Cot-1 DNA blocking reagent

168
Q

Images of metaphase spreads are then acquired with ___________ and __________ to capture the FITC and TRITC fluorescence

A

CCD camera and fluorochrome- specific optical filter sets

169
Q

Differences in fluorescence intensity values between tumor and control DNA represent?

A

gains and losses of specific chromosomes or chromosomal regions

170
Q

A gain of a chromosomal region in the test sample would result in?

A

an increased intensity of green fluorescence

171
Q

A loss within a chromosomal region in the tumor would be indicated by?

A

a shift towards red intensities.

172
Q

What measures fluorescence intensity values along the length of the chromosomes and translates the ratios into chromosome profiles?

A

CGH analysis software

173
Q

The ratio of green to red fluorescence values is used to quantitate what?

A

genetic imbalances in tumor samples.

174
Q

Who is the first person to define the karyotype as the phenotypic appearance of the somatic chromosomes in contrast to their genic contents?

A

Gregorio Levitsky (1931)

175
Q

A long or short term technique to understand the various molecular, cellular and organic functions

A

Tissue culture

176
Q

Simplest form of metaphase chromosome preparation by using lectin as a mitigen like phytohemagglutinin, concanavilin A, pokeweed mitogen etc.

A

Short time lymphocyte culture

177
Q

Short time lymphocyte culture uses what as a mitigen which is similar to what other mitogens?

A

Lectin which is similar to phytohemagglutinin, concanavilin A, pokeweed mitogen etc.

178
Q

Used to detect chromosomal abnormality and rearrangements

A

Metaphase chromosome

179
Q

What are the types of karyotypes?

A

Asymmetric and Symmetric

180
Q

Which between the types of karyotyping show large difference between smaller and larger chromosome in a set?

A

Asymmetric

181
Q

Which between the types of karyotyping have more acrocentric chromosomes?

A

Asymmetric

182
Q

Which between the types of karyotyping show lesser difference between smaller and larger chromosomes in a set?

A

Symmetric

183
Q

Which between the types of karyotyping have more metacentric chromosomes?

A

Symmetric

184
Q

Facultative chromatins

A

Euchromatin

185
Q

Allows to judge the changes in smaller pieces of the chromosomes and related abnormalities which are not visible in analysis

A

Banding

186
Q

Prenatal diagnosis for chromosomal abnormalities, fetal infections and sex determination

A

Amniocentesis

187
Q

Done by obstetricians 10-14 weeks of pregnancy by collecting a small sample of placenta either through a thin needle through the abdomen or a thin tube entering the vagina (similar to that of Pap’s smear)

A

Chorionic Villus Sampling

2nd Year 2nd Term (38 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions