DNA FINGERPRINTING - PowerPoint PPT Presentation

Dna fingerprinting
1 / 13

  • Uploaded on
  • Presentation posted in: General

DNA FINGERPRINTING. Where is the DNA located in the blood?. In the cells ! Specifically, in the nuclei of cells But a red blood cell doesn’t have a nucleus!. So we have to get the DNA from a white blood cell. How do we get the white blood cells separated from the rest of the blood?.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Presentation


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Dna fingerprinting


Dna fingerprinting

  • Where is

    the DNA

    located in

    the blood?

Dna fingerprinting

  • Inthecells!

  • Specifically, in the nuclei of cells

  • But ared blood cell doesn’t have a nucleus!

  • So we have to get the DNA from a white blood cell

Dna fingerprinting

How do we get the white blood cells separated from the rest of the blood?

White blood cells are heavier than red blood cells.

When you put blood in a test tube, break up the RBCs with solution, then centrifuge the tube, the white blood cells all sink to the bottom of the tube, forming a pellet

Remove the pellet and youwillhavegot your white blood cells

Dna fingerprinting

  • We’ve got the white blood cells

  • How do we get the DNA out of the cell?

Dna fingerprinting

  • Add a lysis solution to the pellet

  • Thencentrifugeagain

  • The cell proteins will move towards the bottom of the tube and form a new pellet

  • The DNA will remain floating around in the liquid (called the supernatant)

Dna fingerprinting

  • Add isopropanol to the tube to make the DNA appear in the solution

  • Centrifuge AGAIN

  • DNA will be in the pellet at the bottom of the tube

  • Wash the DNA with ethanol

  • Preserve it in buffer solution

  • The DNA is ready!

Dna fingerprinting1

DNA Fingerprinting

  • DNA fingerprinting begins with treating a sample of DNA with restriction enzymes

  • These enzymes break the DNA into fragments

Dna fingerprinting

  • When these fragments of DNA are then placed in a gel and put through the electrophoresis process, the fragments of their DNA will separate by length

  • Since everyone will have different sizes and numbers of fragments, the pattern those fragments create as they move down the gel will be unique for each person

The pattern created on the gel is the DNA “fingerprint”

Dna fingerprinting

  • Scientistsare able to determine whether two DNA samples are from the same person, related people, or non-related people.

  • Scientists use a small number of sequences of DNA that are known to vary among individuals a great deal, and analyze those to get a certain probability of a match.



  • http://protist.biology.washington.edu/fingerprint/dnaintro.html

Prepared by



  • Kardelen DEMİRCİ

  • Login