Current Genetic Techniques How can we use DNA today? Section 3 - Parts of Chapters 13 & 14

What is genetic engineering? A process that allows scientists to make changes in an organism’s DNA code

How do you get a sample of DNA to use for this? 1) DNA Extraction - Add chemicals to open up the membranes in the cell and isolate the DNA 2) Cut the DNA - Add restriction enzymes to cut the DNA at precise locations (base sequences) so it is a more manageable size

DNA Extraction

Cutting DNA with Enzymes

What is gel electrophoresis? A technique used in genetic engineering that separates DNA fragments by applying an electric charge to a porous gel

Why is gel electrophoresis used? It puts the DNA in a useable form so it can be read Helps us locate a gene of interest Allows us to compare genes

What do you do next? Read the DNA sequence by analyzing the bands on the gel DNA sequencing - Before the gel was run the DNA segment was added to a test tube with DNA polymerase DNA polymerase added new bases that were labeled with colors that could be read from the gel

Now what? 1) DNA fragments can be cut and added to DNA from other organisms in order to make recombinant DNA 2) Copies of genes be made by performing a polymerase chain reaction (PCR) technique

These new techniques allow for… Transgenic organisms Cloning Genetically modified foods DNA fingerprinting

Your turn…. Share with your neighbor one thing that you would like to use these new genetic techniques for My example - figuring out where I got my red hair from; or combining my two favorite fruits

Human Traits How to use and design a Pedigree Chart

What do you see?

Human Pedigrees Diagrams showing the phenotypes of a particular trait over several generations of a family line Females - circle Males - squares Colored in - individual showing the trait Clear - individual not showing the trait Half colored in - carrier of the trait

Is individual 1 TT or Tt?

Write out the possible Punnett Squares and see….. tt TTt ttt tt TTt T Which one works with the family? 1 OR 2?

What if the trait is held on the X chromosome?

Your turn… Begin the worksheets on Pedigrees and the Green Gene with your seat partners and start the one for homework