#geneticssl

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-Uses

-Process

-Benefits

-Ethical issues (arguments for and against)

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DNA Profiling

DNA Profiling is a technique by which individuals are identified on the basis of their respective DNA profiles. For example when parents want to know if their child matches their DNA.

1) DNA sample is collected and amplified via PCR

2) Restriction enzymes used to generate fragments 

3) Unique fragments lengths are shown through STRs (long stretches of DNA made up repeating fragments)

4) Fragments can be separated through gel electrophoresis

5) DNA is compared and analyzed

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Gel electrophoresis

Gel electrophoresis is a technique which is used to separate fragments of DNA according to size.

1) Samples of fragmented DNA are placed in the wells of agarose gel.

2) The gel is placed in a buffering solution and an electrical current is passed through the gel.

3) DNA being negatively charged due to phosphate moves to the positive anode

4) Smaller fragments are less impeded by the gel matrix and move faster in the gel

5) Fragments are separated.

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Polymerase Chain Reaction

PCR- Polymerase chain reaction: Produces large quantities of a specific target sequence of DNA useful when only a small amount of DNA is available for testing

1) Denaturation: DNA sample is heated to separate it into two strands 2) Annealing DNA primers attach to opposite ends of the targeting sequences

3) Elongation A heat tolerant DNA polymerase copies the strands

This is one cycle, but it is repeated billions of times to produce lots of DNA