5: Molecular Diagnostics for Forensics and Genetics (FINALS) Flashcards
In molecular biology, this refers to the study of the human chromosome
Genetic
In genetics, this refers to the process of examining complete set of cells in an organism
Karyotyping
In genetics, what are the characteristics of chromosomes studied
idk but list it ghorl
- physical size
- structure
- main behavior
Most common application of molecular techniques in genetics
to identify a CHANGE in chromosomes
or specific mutations in the chromosome
Enumerate the traditional process in studying genes/chromosomes
dapat alam mo na to malaki ka na
- Cell culture
- Metaphase arrest
- Hypotonic swelling
- Fixation
- Chromosome Spread
- Aging
- Photomicroscopy
- Reporting
Review
Identify the reagent used in cell culture
Phytohemagglutinin (PHA)
Review
Reagent/inhibitor used to arrest cell division at metaphase
Colcemid
Review
Reagent for hypotonic swelling
Hypotonic buffer
eme dapat 0.075M KCl at 37° C for 10-20 mins
Reagent for Fixation
Carnoy’s fixative
(3:1 ; absolute methanol: glacial acetic acid)
In terms of the manner of reporting, what parameters are considered?
- pairing of the chromosomes
- ba(n)ding patterns
a new technique under the
molecular biology used to match chromosomes
In Situ Hybridization (ISH)
In its earliest development, ISH used ________ probes as target labels
radiolabeled (radioactive substances)
due to the harmful effects of radiolabeled probes what was the alternative probe used?
Fluorescence probes
Type of ISH which uses flurorescence probes
Fluorescence In Situ Hybridization
sis kung mali ka ewan nalang
➢ a tagging technique
➢ A method on how we add the probe into the
sample or reagent
➢ It is a process wherein the DNA polymerase I is used to replace some nucleotides of
DNA sequences
Nick Translation
STUDY MO GENERAL PROCEDURE NG FISH
shoo shoo
congrats kung binasa mo, kung hindi magbasa ka na
Nick translation -> denaturation -> required antibodies (labeled) -> visualization (microscope)
Main advantage of FISH
➢ specifically see the exact location of the gene
➢ less hazardous (compared to using radiolabeled probes
Enumerate the advanced applications of FISH
- INTERPHASE FISH
- WCP (Whole Chromosome Painting)
- MFISH (Multicolor – FISH)
- SKY (Spectral Karyotyping)
- ALL – TELOMERE – FISH
- Comparative Genomic Hybridization
Advanced Application of FISH
not arrested in the metaphase stage; instead, what is checked here is the interphase stage.
Interphase FISH
basic btch
Adv. Appli of FISH
Advantages of Interphase FISH
- NO cell culture required, thus
the diagnosis is much rapid - You will proceed immediately to
hybridization (in situ technique is directly
performed)
Adv. Application of FISH
In this application, different or many types of
probes are used from a SINGLE chromosome
WCP (Whole Chromosome Painting)
Adv. Application of FISH
Main principle of WCP
On the single chromosome, there are
LOTS of UNIQUE DNA associated with
it.
Adv. Application of FISH
Main advantage of WCP
for seeing or looking for any rearrangements (i.e.,
interchanged long and short arms) in the
chromosome
Adv. Application of FISH
Almost the same as WCP but the main difference is that there is a system/software installed
Multicolor FISH (MFISH)
Adv. Application of FISH
Main advantages of MFISH
- automated (has computer-assisted system)
- Fixed profile, which you’ll only need to compare to the sample
Adv. Application of FISH
- permits the display and identification of all 24 human chromosomes using painting probes
- multiple chromosomal aberrations are detected
Spectral Karyotyping
definition from taken fr both lec and cyto
Adv. Application of FISH
Main advantage of SKY
allows the observation of multiple chromosomal aberratios or changes
Adv. Application of FISH
The main probe/label is a telomere probe
ALL - Telomere FISH
Adv. Application of FISH
Detects six base repeats present at the ends of all chromosome
ALL - Telomere FISH
Adv. Application of FISH
Main advantage of All-Telomere FISH
used as a confirmatory assay (presence/absence of telomeric regions)
Adv. Application of FISH
you simply compare the DNA content of
a differentially labeled normal and abnormal
cell population
Comparative Genomic Hybridization
Enumerate the 3 Main Applications of FISH
- DIAGNOSIS
- PROGNOSIS
- EVALUATE
2 sis ate