DNA TYPING

NUR HANISAH BINTI ZAINOREN

OBJECTIVE1. History

2. Definition

3. Techniques

4. Applications

5. Advantages

6. Disadvantages

PROFESSOR ALEC JEFFREY

first application of DNA

typing in forensic science

DEFINITION• A procedure

wherein DNA extracted from a biological sample obtained from an individual is analyzed

• DNA is processed to generate a pattern for each person that is generally termed as a 'DNA profile'

TECHNIQUES1. RFLP - Restriction

Fragment Length Polymorphism

2. PCR - Polymerase Chain Reaction

3. STR - Short Tandem Repeats

4. Mitochondrial DNA Analysis

5. Rapid DNA ID Microchip-Based Genetic Detectors

RFLPDNA is cut into fragments by

restriction enzymes

Chops the DNA in two at every place where the GCGC pattern occurs

GCGCATTGTTGCGCAAGAGCGC

GCGCATTGAATGCAAGTAGCGC

1st person:

2nd person:

GCGCATTGTTGCGCAAGAGCGC

GCGCATTGAATGCAAGTAGCGC

1st person:

2nd person:

GCGCATTGTTGCGCAAGAGCGC

GCGCATTGAATGCAAGTAGCGC

1st person:

2nd person:

GCGCATTGTTGCGCAAGAGCGC

GCGCATTGAATGCAAGTAGCGC

1st person:

2nd person:

2 small fragments

1 large fragments

STR

SOURCES OF BIOLOGICAL EVIDENCES• Blood• Teeth• Semen• Saliva• Hair• Urine• Bone• Tissue

PROCEDURE - COLLECTION & FORWARDING OF SAMPLES

• To be done.• As told by my

lecturer, this is actually the important part for a doctor to know

APPLICATIONS• Paternity disputes• Maternity resolution• Establishment of

biological relationship• Identification of rapist• Identification of bodies in

exhumation cases

DNA TYPING IN PATERNITY TEST

ADVANTAGES• Require small sample• Can be applied on

very old stains• Most conclusive

method

DISADVANTAGES• Cannot differentiate

identical twins• Very expensive• Interpretation of

results requires a great deal of expertise and experience

REFERENCES

THANK YOU