Forensic Serology

Forensic Serology the study of Blood for Crime Scene/Evidence purposes

How to extract DNA from blood.

DNA can be extracted from blood (if white blood cells which always contain a nucleus are present). Blood is commonly used in DNA testing, as per the following steps:

1. Blood samples are collected from the victim, defendant, and crime scene.

2. White blood cells are separated from red blood cells.

3. DNA is extracted from the nuclei of white blood cells.

4. A restrictive enzyme is used to cut fragments of the DNA strand.

5. DNA fragments are put into a bed of gel with electrodes at either end.

6. Electric current sorts DNA fragments by length.

7. An absorbent blotter soaks up the imprint; it is radioactively treated, and an X-ray photograph (called an autoradiograph) is produced.

Different types of blood cannot be mixed because that would result in the blood clumping together. This can result in DEATH! So far there has been more then 100 different blood factors discovered by scientists, doctors and serologists.

Did You Know?

No two individuals have the same combination of blood factors except for identical twins. The blood factors are genetically controlled(They're in your genes).