DNA Fingerprinting

Daniel LimLin Siqi

Si HongboWang Chengxu

Guideline

• Definition of DNA Fingerprinting

• The techniques and methods

• When to use

• Problem with it

• Interesting Cases

Definition

• The process of comparing the nucleotide sequences of different DNA samples to find out if the samples are from the same individual or not.

• It was invented by Sir Alec Jeffreys at the University of Leicester in 1985.

Techniques and Methods

• RFLP Analysis

• STR Analysis

RFLP Analysis

• Performing a Southern Blot

• Making a Radioactive Probe

• Creating a Hybridization Reaction

• VNTRs (Variable Number Tandem Repeats)

Performing a Southern Blot

http://protist.biology.washington.edu/fingerprint/blot.gif

Making a Radioactive Probe

Creating a Hybridization Reaction

VNTRs

STR Analysis

• Short Tandem Repeats

• PCR Amplication

• Electrophoresis

When to use it?

• Forensic evidence --- Criminal Identification

• Parenthood disputes --- Paternity and Maternity Establishment

Problem with it

• Generate a high probability

• Problems with this:

1. Population genetics

2. Technical difficulties

Interesting Cases

• In the 1920s, Anna Anderson claimed that she was Princess Anastasia Romanov of Russia; in the 1980s after her death, samples of her tissue that had been stored at a Charlottesville, Virginia hospital following a medical procedure were tested using DNA fingerprinting and showed that she bore no relation to the Romanovs.

Interesting Cases

• In 1987, British baker Colin Pitchfork was the first criminal caught using DNA fingerprinting in Leicester, the city where it was first discovered

Interesting Cases

• In 1994, Royal Canadian Mounted Police (RCMP) detectives successfully tested hairs from a cat known as “Snowball”, and used the test to link a man to the murder of his wife, thus marking for the first time in forensic history the use of non-human DNA to identify a criminal.

Q & A

Bibliography

• Campbell, N, A. Reece, J, B. Biology, Seventh Edition, 2005, Pearson.

• Audesirk, T. Audesirk, G. Byers, B, E. Biology: Life on Earth, Seventh Edition, 2005, Pearson.

• http://www.cartoonstock.com/• http://en.wikipedia.org/wiki/

Genetic_fingerprinting• http://protist.biology.washington.edu/fingerprint