Introduction to Biotechnology - Mr. Tsigaridis

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Introduction to
Biotechnology
Mr. Tsigaridis
Why use it?
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What are some of the advantages to
biotechnologies in genetics?
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The offer us advances in pharmacogenomics
They allow individuals to identify problems early
on
They allow for identification of changes at the
genetic level
Why use it?
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What are some of the disadvantages to
biotechnologies in genetics?
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They create ethical issues (euthanasia,
abortions)
WE DON’T KNOW
What is out there?
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The biotechnologies that we are going to look at
in this presentation are as follows:
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Amniocentesis
Fetoscopy
Ultra Sound
Chorionic Villus Sampling
PCR
SDS-PAGE
Adenovidus Vectoring (gene therapy)
DNA Micro Array
Amniocentesis
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What is amniocentesis
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It is a medical procedure used in prenatal
diagnostics
A small amount of amniotic fluid is sampled
The fluid contains fetal tissue
It is extracted through the amnion (sac)
DNA is then examined for abnormalities
Amniocentesis
Amniocentesis Application
Amniocentesis Application
 What can it be used for?
 It can be used to identify the sex of a fetus
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It can be used to identify genetic disorders, either
from karyotyping or from genetic analysis
(mapping of genome)
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Is this good or bad (talk about it with a partner,
and then bring your ideas back to me)
Some of the dangers
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Infection can occur from the puncture
Incomplete healing can cause leakage and
infection of the amniotic sac
Fetoscopy
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What is a fetoscopy
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This is an endoscopic procedure that allows the
medical professional access to the fetus,
amniotic cavity, the umbilical cord, and the fetal
side of the placenta
Fetoscopy
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What is it used for?
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It allows for medical interventions such as:
Biopsy
Laser occlusion of damaged blood vessels
Fetoscopy
An important use
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It can also be used to perform blood
transfusions of fetuses
It can save the fetuses life
It can also be a first step in identifying
genetic disorders that a fetus may have
Dangers of fetoscopies
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The incisions may become infected
Leakage of the amniotic fluid into the body
cavity may occur
Chorionic Villus Sampling
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Is a form of prenatal diagnostic testing
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It is used to identify prenatal chromosomal
and genetic disorders
How it is done?
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A sample of the chorionic villus is taken
and tested
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What is the chorionic villus?
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Placental Tissue
When it is done?
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Its advantage comes with its timing
It can happen from weeks 10-13 after the
last period
This is a better technique than
amniocentesis because that can only
happen from weeks 15-18
CSV – Chorionic Villus Sampling
Reasons for having it done
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Mother's age of 35 years or greater
Abnormal first trimester screen results
Increased nuchal translucency or other
abnormal ultrasound findings
Family history of a chromosomal
abnormalities or other genetic disorders
Parents are known carriers for a genetic
disorder
UltraSound
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Is cyclic sound pressure with a frequency
that is greater than that of human hearing
UltraSound
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The production of ultrasound is used in
many different fields
It is used to penetrate a medium and
measure the reflection signature
This reveals information about the inner
structure of the medium
The old ultrasound
The new ultrasound
Other uses
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Studying the earth
Cleaning teeth
Breaking kidney/gull stones
PCR – Polymerase Chain Reaction
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It is widely used in molecular biology
Created by Kary Mullis
This allows for amplification of small
amounts of DNA
The secret
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Thermus
Aquatiucs
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AKA - TAQ
Why Taq?
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The reason they wanted to use this
bacteria was because it lives at such high
temperatures
The Polymerase (the enzyme that lays
down nucleotides) works at high
temperature
Higher than that of DNAs denaturing point
The process
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What goes in the tube?
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DNA of interest
Primers
Taq Polymerase
Nucleotides (lots of them)
Water
Magnesium
Then what happens
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They put the eppendorf
tubes into the PCR
cycler
The process is
repeated many times
Why it works?
Some Math
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20 = 1
21 = 2
22 = 4
23 = 8
223 = 8,388,608
236 = 68,719,476,736
What are the uses
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Studying genes
Forensics
Today – basically all gene related research
SDS-PAGE
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Sodium dodecyl sulfate polyacrylamide
gel electrophoresis, is a technique used
in biochemistry, genetics and molecular
biology to separate proteins according to
their electrophoretic mobility
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They are separated as a function of their
size
What is it used for?
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Genetic testing
Paternity testing
Forensics
The Apparatus
The Point
DNA Micro Array
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A DNA microarray is an arrayed series of
microscopic spots of DNA Oligonucleotides
Each spot contains picomoles of a specific
unique sequence, such a stretch of a gene
sequence
What is a picomole?
The breakdown
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pico p 10-12
nano n 10-9
micro µ 10-6
milli m 10-3
centi c 10-2
deci d 10-1
kilo k 103
mega M 106
giga G 109
tera T 1012
What is it used for
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It is used to do many thousands of
experiments at once
It can be used to identify if a certain gene is
present
Or it can be used to identify if a gene is
expressed, over expressed or
underexpressed
What it looks like
Gene Therapy – Adenovirus Vector
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Viral vectors are a tool commonly used by
molecular biologists to deliver genetic
material into cells
A common virus is adenovirus, HSV
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