4.4 Genetic engineering and biotechnology

http://www.npr.org/templates/story/story.php?storyId=9798603

DNA profiling Identify natural variations found in every person’s DNA Use variable number of tandem repeats (VNTR) Short, repeated sequences of nucleotides e.g. CACACA, ATTCGATTCG Number of repeats are highly variable No known function 1984 Alec Jeffries

4.4 How is DNA profiling useful? Forensic investigations Collect samples such as blood or semen to use as evidence for court case Investigate paternity The bands on the child's fragments are either found on the mother or the male1.

DNA profiling 1. Isolate DNA from biological materials from the crime scene (hair, blood, etc.) and possible suspects

DNA profiling 2. Polymerase chain reaction Purpose: make copies of DNA Two strands of DNA separate (DNA denaturation due to high temperature) DNA polymerase from Thermus aquaticus (a bacteria that lives in hot springs) Synthesizes new DNA strand by using complementary strand as template http://highered.mcgraw-hill.com/sites/0072556781/student_view0/chapter14/animation_quiz_6.html

http://www.cnpg.com/video/flatfiles/539/

DNA fingerprinting process 3. Cut the DNA into small fragments via restriction enzymes 4. Gel electrophoresis Method of separating mixture of DNA Mixture placed in well Electric field is applied gel via electrodes Separate according to size and charge (highly charged molecules move faster)

Will our gel look like this? No – we have all the DNA How do we separate individuals? What do we need to identify VNTR? Single stranded DNA + probe with complementary nucleotides of interest

DNA profiling 5. Make single stranded DNA Application of external stress: strong compound (acid/base) 6. Add radioactive probe DNA fragment containing nucleotide bases complementary to gene of interest Hybridization

Try this! DNA profiling – M. Anderson http://www.youtube.com/watch?v=DbR9xMXuK7c Gel electrophoresis virtual lab http://learn.genetics.utah.edu/content/labs/gel/

4.4 Genetic engineering and biotechnology Blog: Describe the process of DNA profiling. Feedback distributer: Fernanda

4.4.5 The Human Genome Project Begun formally in 1990 the international projects aims Completed April 2003 Findings: Number and loci of all genes in our genome (30,000). Fewer than expected => complex relationship between genes. New proteins and functions discovered. Better drugs design using knowledge of protein structure DNA comparisons can be made with other species. Closely related species share more similarities in the DNA sequence. Used to infer evolutionary history.

The Human Genome Project Genetic ‘report card’: contains individual genetic information Who should have access? How should they use it?

GMO & Cloning Feedback distributer: Diego If your topic is GMO, please sit in the middle. Announcement: Learning Log

Gene transfer Universality of genetic code allows genes to be transferred from one organism to the other Genes are transferred between species, the amino acid sequence of polypetides translated from them is unchanged

Gene transfer small (2 - 30 genes) loops of bacterial DNA plasmids = vector = medium by which genes of interest are transferred to host small (2 - 30 genes) loops of bacterial DNA a host cell (bacterium): receives a gene of interest via a vector replicates repeatedly, passing on gene of interest to offspring

Gene transfer restriction enzymes DNA ligase produced naturally by bacteria as defense against viruses used to cut the desired section of the DNA recognizes unique sequences of DNA in plasmid and in gene of interest Cuts complementary sticky ends in gene of interest and plasmid allow incorporation of gene of interest into plasmids DNA ligase creates covalent bonds joining together gene of interest within plasmid, producing recombinant DNA GMO = genetically modified organism

Monsanto America’s BIG Agricultural biotechnology cooperation “Roundup”: Crops genetically designed to tolerate herbicide 80% of soybean, corn, cotton, sugar beets, and canola seeds grown in US are from Monsanto

Gene patenting Patent = Intellectual property right Right to prevent others from making, using selling patented product without permission

Discussion Benefits Controversies Questions:

Cloning Clone = group of genetically identical organisms or group of cells derived from single parent

Dolly – Word’s most famous sheep Born 1996 Three sheep: DNA donor, Egg cell donor, surrogate mother Electric shock causes two cell membranes to fuse and mitosis to trigger Embryo implanted into surrogate mother http://learn.genetics.utah.edu/content/tech/cloning/

Why clone? Cloning for medical purposes Cloning animal models of disease: create multiple copies of transgenic organism with disease causing mutation in genes “Pharming” for drug production Farm animals such as cows, sheep and goats are genetically engineered to produce drugs or proteins Cloning stem cells for research Stem cells: unspecialized cells that continually reproduce themselves and differentiate under appropriate conditions Contain human gene for making important proteins (insulin, growth hormone). Isolate protein from milk

Why clone? Retrieving endangered or extinct species Cloning dinosaurs? Need well preserved DNA Reproducing a deceased pet Cat cloning service in US

Why clone? Cloning humans? Couples that can’t have child Couples that have lost child Does everyone have right to have children, regardless of how they are created? Is human cloning playing with nature?