DNA fingerprinting

Southern Blotting

Detects specific sequences of nucleotides in DNA samples.

Who introduced Southern blotting?

Edwin Southern in 1975

What happened in the 1980s?

The first court case was decided using DNA fingerprint to match a child to a parent. This influenced using DNA fingerprinting in solving crimes.

What does the Innocence Project work on?

Overturning criminal convictions based solely on hair analysis.

When did the Innocence Project start?

1992

When was PCR discovered?

1983

What is PCR?

Polymerase chain reaction - repetitive process of heating and cooling a DNA sample, which Artificially causes a gene to be replicated.

Why is PCR beneficial?

More efficient method for replicating a gene. It also allows significant testing to be performed on samples that only contain small amounts of DNA.

What has gel electrophoresis been replaced with?

STRs - short tandem repeats - because they are more efficient since they use lasers.

What is unique about STRs?

They are unique to each individual and can be converted to a graph.

Steps of Southern Blotting

Cut the DNA at specific locations with restriction enzymes. Place samples into gel. Electrically charging the DNA will cause the DNA fragments to move across the gel in a process known as gel electrophoresis. the result will be a pattern known as a DNA fingerprint.