Thymus DNA Extractions

Materials

    Fresh thymus

    Blender

    Beaker

    Sugar

    Pipet

    Centrifuge tube with cap

    Bufferin (325mg)

    Knife

    Graduated cylinders (10ml,100ml)

    Epsom salts

    Distilled water

    Centrifuge

    95% ice cold ethanol

    15 ml test tubetest tube rack or beaker

    Palmolive detergent

    Non-iodized salt

Solutions

Prep buffer solution:

    57 g granulated sugar

    1 buffered aspirin

    3 g epsom salts

    Add distilled water for a total of 500 ml

10% detergent solution:

    90 ml distilled water

    10 ml Palmolive detergent

Salt solution:

    29.2 g non-iodized salt

    Add distilled water for a total volume of 250 ml

Protocol

    Cut out a chunk of liver or thymus 1 inch square and place in the blender.

    Add 100 -150 ml prep buffer and 10 ml detergent solution to the blender.

    Blend for 1 minute or until the mixture is smooth.

    Pour the mixture into a beaker.

    Transfer 1 ml of the mixture to a centrifuge tube.

    Add 2 ml of salt solution, cap, and shake for 2 minutes.

    Centrifuge for 7 minutes in a balanced centrifuge.

    Carefully remove the tube from the centrifuge and note the two layers:

        Lower layer - pellet

        *upper layer - liquid (supernatant) and what has the DNA in it.

    Pipet or carefully pour the liquid into a clean test tube.

    Pour 5 ml ice cold ethanol carefully down the side of the tube to form a layer.

    Let the mixture sit undisturbed for a minute or two.

    The DNA will float in the alcohol. The DNA of the thymus will be long threads that easily spool.

Modified from: "Generic, All Purpose DNA Extraction from Meat Protocol" Judy Brown

"Mammalian DNA Extraction" Theresa Knapp