MURDER RAPE AND DNA

Murder, Rape, and DNA


DNA is the information needed by a cell in order to reproduce an
identical offspring. In some crimes detectives have no evidence or
fingerprints to tell who had committed a crime. Now there is a way of finding
who has committed the crime by a method called DNA Typing. DNA Typing
is finding bacteria or blood on clothing or skin and amplifying the gene. This
process was pioneered in the 1980's by a Scientist named Alec Jeffreys.

If blood, sperm, or any other human cells are left at the scene of a
crime, the DNA in the cells can be analyzed and compared with some DNA
taken from the suspect's blood. If they match, this information and testimony
of a scientist can be used to convict a rapist or murderer.

In the O.J. Simpson case DNA Typing was used. There was blood
found on various areas at the crime scene. The investigators gathered the
evidence, and took it to the laboratory where it was analyzed. The jury
determined that the samples were contaminated because of the way they were
handled.

DNA Typing is not perfect. There are many loop holes in it. An
example is the O.J. Simpson trial. During the process the DNA may be
tampered with or damaged.

In most rape cases DNA Typing is used by taking semen off the body
of clothes then amplifying the genes. The machine that copies the DNA is
called the PCR. The DNA is then cut and placed the wells in trays. PCR
copies the small pieces of DNA. It is performed by a blotting process. This
process has 21 different catogories.

Other tests include those for tracing genetic diseases within families,
finding the genes that cause genetic diseases. DNA Typing can also prove
the relationship with families.

DNA Typing is becoming more common than ever. This process is
helping to free convicted people of crimes they may not have committed by
taking samples of the prisoners DNA and comparing it with the evidence left
at the crime scene.

Jonathan Dewees
February 16, 1997