DNA Profiling and Gel Electrophoresis Biology Accelerated 2006 Biotechnology Genetics Some slides taken and edited from Maria Hall, Julie Basil and Karen Wolfe

Think Pair Share What is DNA profiling? How is DNA profiling used? How is the process performed?

Commonly Used Techniques Each of the following will be explained in further detail  Restriction enzymes  Recombinant DNA (using plasmids)  Gel electrophoresis  DNA profiling  DNA sequencing

Restriction Enzymes “molecular scissors” Enzymes found in bacteria Used by the bacterium as a defense against “foreign” DNA Cut DNA at very specific places or sequences (called restriction sites) The “cut” DNA pieces can have either  Blunt ends  Sticky ends

Restriction Enzymes also known as restriction endonucleases named for the bacteria where they originally came from ex: EcoRI

Why cut DNA? DNA is cut so that another piece of DNA can be inserted The “other” DNA contains the gene you want to copy

Citation Greatest Discoveries with Bill Nye: Genetics. Discovery Channel School unitedstreaming. 23 January 2006

Citation (MLA) Biologix: Manipulating DNA. United Learning unitedstreaming. 23 January 2006

How restriction enzymes work

cut each DNA strand at different bases--creates “sticky ends” open “flap” of DNA can readily bind with a complementary “flap” some restriction enzymes make “blunt ends”

RFLPs abbreviation pronounced “rifflips” stands for restriction fragment length polymorphisms restriction fragment =  fragment of DNA cut with restriction enzymes length polymorphisms =  many different lengths

Gel electrophoresis

technique used to separate strands of DNA, RNA or protein according to their size For DNA, samples first need to be purified and cut with restriction enzymes DNA placed into a well at one end of an agarose gel (like jello) the gel acts as a strainer

Citation Greatest Discoveries with Bill Nye: Genetics. Discovery Channel School unitedstreaming. 23 January 2006

Electrophoresis animation Electrophoresis Animation Electrophoresis Animation 2 enes/index.shtml enes/index.shtml

Self Check and Review In your study group of 3 students discuss the following issues form a consensus and write down what you learned:  DNA Profiling Why is it done? What are its uses? What is needed to do DNA profiling (materials). How is it done? (steps in the process)

PCR Clip Citation (MLA) Biologix: Manipulating DNA. United Learning unitedstreaming. 23 January 2006

Citation (MLA) Biologix: Manipulating DNA. United Learning unitedstreaming. 23 January 2006