DNA Technology
How DNA is Analyzed in
today’s world?
DNA Technology Uses
 Since
discovery of DNA in 1953,
scientists have analyzed the
structure of DNA.
 DNA fingerprinting - test to identify &
evaluate the genetic information in
living cells.
 DNA analysis used for:
– Crime, forensics, disease, genetics,
paternity.
The First Step

Stage 1:
Cells are broken down
to release DNA
If only a small amount
of DNA available, it
can be amplified or
duplicated using the
polymerase chain
reaction (PCR)
PCR – Polymerase Chain Reaction
 Makes
copies of small fragments
of DNA to work with.
Stage 2

The DNA is cut into fragments using restriction
enzymes.
Each restriction enzyme cuts DNA at a specific base
sequence for all organisms.
 The
sections of DNA that are cut out
are called restriction fragments.
 This
yields thousands of restriction
fragments of all different sizes
because the base sequences being
cut may be far apart (long fragment)
or close together (short fragment).
Stages of DNA Profiling
Stage 3:
 Fragments are
separated by size
using process called
gel electrophoresis.
 DNA fragments
injected into wells
and electric current is
applied along gel.
Electrophoresis



DNA is negatively
charged so it is
attracted to the
positive end of the
gel.
DNA is separated
on basis of size.
The shorter DNA
fragments move
faster than the
longer fragments.
Stages of DNA Profiling
A radioactive
material is added
which combines
with the DNA
fragments to
produce a
fluorescent image.
 A photographic
copy of the DNA
bands is obtained.

Stages of DNA Profiling
Stage 4:
– Patterns or bands are formed in the gel
from small and large fragments.
– Patterns are unique to each individual
and can be used to prove or disprove
paternity, guilt or innocence of a crime,
determining evolutionary history, etc
Uses of DNA Profiling
 DNA
profiling is
used to solve
crimes &
medical
problems
Crime
 Forensic
science is the use of
scientific knowledge in legal
situations.
 The DNA profile of each individual is
highly specific.
 The chances of two people having
exactly the same DNA profile is
30,000 million to 1 (except for
identical twins).
Biological materials used for DNA
profiling






Blood
Hair
Saliva
Semen
Body tissue cells
DNA samples have
been obtained from
vaginal cells
transferred to the
outside of a condom
during sexual
intercourse.
DNA Profiling can solve crimes
The pattern of the DNA profile is then
compared with those of the victim and the
suspect.
 If the profile matches the suspect it
provides strong evidence that the suspect
was present at the crime scene (NB:it
does not prove they committed the
crime).
 If the profile doesn’t match the suspect
then that suspect may be eliminated from
the enquiry.

Whose
going to
the
slammer?
Solving Medical Problems
DNA profiles can be used to determine
whether a particular person is the parent
of a child.
A childs paternity (father) and
maternity(mother) can be determined.
This information can be used in
• Paternity suits
• Inheritance cases
• Immigration cases
Example: A Paternity Test
 By
comparing the DNA profile of a
mother and her child it is possible to
identify DNA fragments in the child
which are absent from the mother and
must therefore have been inherited
from the biological father.
Whose the Daddy?
Practical Uses of DNA
Technology
1.
2.
3.
4.
5.
Pharmaceuticals
Genetically engineered vaccines
Increasing crops
Crops that don’t need fertilizer
Genetically engineered foods
GMOs
Genetically Modified
Organisms
Manipulating DNA


Genetic Engineering
-process of reading
and changing DNA
sequences in an
organism.
Reading the Genetic
Code
– DNA extraction
– Cutting and Labeling
DNA
– Separating DNA
– Reading the DNA
sequence
– Making Copies (PCR –
polymerase chain
reaction)
Transgenic Organisms - organism that
contains genes from other organisms
Transgenic
Bacteria
Transgenic
Plants
Transgenic
animals
Produce
clotting factors
insulin
HGH
Stronger plants More
production
More
production
Pest resistance
Transforming Animal Cells






Can be transformed similar
to plants.
Some eggs are large
enough to physically inject
new DNA by hand. Which
can “Knock Out” a gene
Transgenic organisms
contain genes from other
organisms.
Making onions glow using
jellyfish DNA.
Using bacteria to make
human insulin.
Using genetic modification
to improve food supply
known as GM foods.
Cloning – creating an identical copy
 member
of a population of
genetically identical organisms
produced from a single cell
“Dolly, 1st mammal clone”
“Dolly” was an
important break
through not just
because she was a
mammal.
 Frogs were cloned
back in 1950’s
 Why was dolly so
special?

– Research and answer
this question for me.
CC the Cloned Cat
CC, for "CopyCat" or "Carbon Copy"[1]
(born December 22, 2001), is a
brown tabby and white domestic
shorthair and the first cloned pet.
Born at the College of Veterinary
Medicine at Texas A&M University
Embryo that became CC was the only one of 87
embryos produced in this research project that
developed into a full-term pregnancy after being
transferred to surrogate mothers.
Human Genome Project


1.
1990-2006
2 goals:
Determine the
nucleotide sequence
of entire human
genome
1. 3 billion nucleotide
pairs, 100,000 genes
2.
Map location of
every gene on each
chromosome
Benefits
Compare human genome with other
species to give information on:
1. Organization of genome
2. How gene expression controlled
3. Control of cell growth and
differentiation.
4. How evolution occurs