DNA Fingerprintin

g!By: Megan Riehle

Overall Process

http://www.youtube.com/watch?v=drC7rR7CIBg

Video of DNA Fingerprinting Process

Isolation of the DNA!

In order for a DNA fingerprint to be made you must first gather DNA from the person you are fingerprinting.

There are many things you could use to gather DNA…

1. Blood2. Hair3. Skin4. Saliva5. Or any other cell

with DNA in it.

Human Cheek Cells

Restriction Enzymes

• Used to cut DNA into pieces that are specific to each individual persons DNA.

• Specific Enzymes cut the DNA into pieces at specific places as well. For Example…

• EcoR1 cuts only when the sequence GAATTC occurs.

Restriction Enzymes Continued!

• Sticky Ends are made by cutting the DNA in a staggered manner and they have a one stranded DNA sequence that have complementary nucleotides

• Blunt Ends are made by cutting the DNA directly down the middle of two nucleotides

Gel Electrophoresis

• Samples of cut DNA are placed in an agarose gel

• Electricity is added to the gel and the DNA travels to the positive pole and they are spread out according to size.

Transfer to Nylon Screen• Because the gels are so hard to

manipulate the DNA pattern is transferred to a nylon sheet using the process of southern blotting

• Nylon is added to the agarose gel and then a piece of paper is added on top this absorbs the DNA bands onto the nylon.

Probing and X-Ray• Probes are radioactive particles that

bind themselves to the main sequence.

• Extra probes that are left over are removed and what is left is only the DNA chain needed to make the fingerprint

• This can be scanned by an X-ray machine and it will produce a picture of the DNA fingerprint

Examples of DNA Fingerprints!

Uses for DNA Fingerprints

• Paternity Testing• Determining who committed a crime• Diagnosis of inherited disorders• Developing Cures for inherited

disorders

Ethical Concerns

• People worry that the use of DNA will eventually lead to discrimination using DNA also known as genoism.

• People could be denied health care, an education, a job etc.

Crime Scene Investigation!!!!

http://www.teachersdomain.org/asset/tdc02_int_creatednafp2/

TEST YOUR ABILITY TO DISCOVER THE CULPRIT

OF THIS TERRIBLE CRIME USING WHAT YOU HAVE

LEARNED ON DNA FINGERPRINTING!