DNA fingerprinting is a technique that allows identification of an individual from biological samples based on their unique DNA fingerprint. It works by detecting variations in short tandem repeats (STRs) in the DNA, which differ in length between individuals. The process involves extracting DNA from a sample, using restriction enzymes to cut the DNA at specific sites, separating the fragments via gel electrophoresis, and amplifying the STR regions via polymerase chain reaction to facilitate comparison to known DNA profiles. DNA fingerprinting has applications in forensics, paternity testing, and medical diagnosis of inherited disorders, but risks discrimination and privacy issues if not properly regulated and restricted.

1. DNA Fingerprinting
by : Eman abdelshafy
supervised by : Dr Randa Hussien ,
Dr:Heba Pasha

2. DNA fingerprinting
a useful tool allows us to
identify an individual from
any biological samples
based on the unique
fingerprint of their DNA.
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3. Background
• Almost every cell in our body contains
our DNA that carry all the genetics
information.
• 3 billion of nitrogen base pair ATGC build
human DNA.
• On average, about 99.9 per cent of the DNA
between two humans is the same.
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4. ◦ The remaining percentage about 5 million
base pairs is what makes us unique
(unless you are an identical twin!).
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5. Minisatellites (1980)
◦ are short sequences (10-60 base pairs long) of
repetitive DNA .
◦ show greater variation from one person to the
next than other parts of the genome
◦ This variation is exhibited in the number of
repeated units or in the minisatellite sequence.
◦ DNA fingerprinting uses such VNTRs((Variable
Number of Tandem Repeats) from an
unknown DNA sample to compare and match
with the known.
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6. DNA fingerprinting`
◦ DNA fingerprinting was invented
in 1984 by Professor Sir Alec
Jeffreys after he realised you
could detect variations in human
DNA, in the form of these
minisatellites.
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7. OUR PROCESS IS EASY
Use restriction enzymes , cut a DNA fragment at specific
sites which it recognizes. Specifically, these regions are
called STRs, or short tandem repeats, The number of times
the sequence is repeated is unique to each individual,
giving each of us fragments of different lengths.
gel electrophoresis technique this
technique employs electric current to
move the DNA fragments over a gel-
based matrix.
Extract DNA from a sample of any human
material, usually blood.
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Polymerase Chain Reaction (PCR): replicate and amplify
the DNA sample inside the lap

8. “
Technique of DNA fingerprinting
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9. Applications
Forensic
investigation
Paternity test
medicine
diagnose inherited
disorders such as
Sickle cell anemia
, Alzheimer ,
Huntington's
disease . Recently
DNA fingerprinting
is used in breast
cancer detection .
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10. Disadvantages and risks of DNA
Fingerprinting
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Discrimination
against an
individual based
on their race,
ethnicity, origin,
or health risks.
privacy rights
if proper methods are not
put in place to strictly
restrict the access to DNA
profiles in proper
circumstances, then many
human and privacy rights
may be put in concern, and
the public will face many
social issues.

11. THANK YOU
😉
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