WHO IS OJ SIMPSON???

1. WHO IS OJ SIMPSON??? • O. J. Simpson was a Hall of Fame football player • Running back for the Buffalo Bills (U.S.C) • Major motion pictures and in television commercials • In June, 1994, Simpson was accused of murdering his ex-wife, Nicole Brown Simpson, and her companion, Ron Goldman. • At the trial which took place a year after the deaths, DNA fingerprinting evidence was presented for the first time in a major case. • Blood found of the door of Simpson's Ford Bronco matched the blood found at the crime scene as established by DNA testing. • The same blood was found adjacent to a shoeprint fitting Simpson's shoe size and on other articles at the crime scene.

2. O.J. Simpson capital murder case,1/95-9/95 • Odds of blood in Ford Bronco not being R. Goldman’s: • 6.5 billion to 1 • Odds of blood on socks in bedroom not being N. Brown-Simpson’s: • 8.5 billion to 1 • Odds of blood on glove not being from R. Goldman, N. Brown-Simpson, and O.J. Simpson: • 21.5 billion to 1 • Number of people on planet earth: • 7.1 billion • Odds of being struck by lightning in the U.S.: • 2.8 million to 1 • Odds of winning the Lottery: • 76 million to 1 • Odds of getting killed driving to the gas station to buy a lottery ticket • 4.5 million to 1

3. DNA Evidence

4. Figure 12.12B Honors Biology: DNA Technology and Society

5. Genetic Engineering HOW AND WHY DO SCIENTISTS MANIPULATE DNA IN LIVING CELLS? • Increase the yield from plants and animals (milk, beef, chicken, corn, soybeans, etc) • Disease and pest prevention/resistance • Cloning • Medical Research • Gene Therapy • Genetic Testing • Personal identification (DNA fingerprint)

6. 14.3 Manipulating DNA • Cutting, Separating and Reading DNA • Restriction Enzymes • Gel Electrophoresis • Probes

7. Enzymes are essential tools in DNA technology 0 Restriction enzymes (endonucleases) • Made by bacteria to cut out foreign DNA • cut DNA at specific sequences – used like molecular scissors • Recognition sequences: 4 to 6 bp’s long • Some cut and leave “sticky ends” • Bacteria methylate A’s and C’s to protect own DNA from being cut up • Ex: EcoR1 DNA ligase • used to “paste” DNA fragments together Restriction enzyme animation

8. RESTRICTION ENZYMES aka Molecular Scissors

9. 0 Gel electrophoresis sorts DNA fragments by size • a molecular sieve (jello) to separate chunks of DNA based on size • restriction enzymes used to chop up DNA into RFLP’s • RFLP: restriction fragment length polymorphism • process utilizes negative charge of DNA to move pieces thru the gel • bigger pieces stay close to origin, smaller pieces move farther toward the positive end • result is a DNA fingerprint (bar code) of your specific DNA pieces…everyone’s DNA will chop up differently fingerprint is unique RFLP animation

10. DNA Fingerprinting • Restriction enzymes are used to cut the DNA into fragments containing genes and repeats • The restriction fragments are separated according to size using gel electrophoresis • The DNA fragments containing repeats are then labeled using radioactive probes. This labeling produces a series of bands – the DNA fingerprint.

12. DNA Fingerprinting

13. 0 1 2 RFLP’s used to detect differences in DNA sequences • Used in crime scene investigations to show guilt or innocence of suspect • Body fluids left behind are processed and analyzed through gel electrophoresis

14. DNA Probes Can Detect Harmful Alleles 0 • Radioactive probes can reveal DNA bands of interest on a gel • Used in genetic screening tests • Huntington’s Disease • Cystic Fibrosis #3. DNA bands treated to separate double strands. Single strands blotted off onto filter paper. #4. Blotted paper is treated with radioactive probe (complimentary to gene sequence of disease causing gene) Probe attaches to RFLP’s from original gene …get several bands #5. Unattached probe rinsed off. Photographic film placed on blot paper. Radioactivity exposes film, forms image corresponding to DNA which base-paired with probe person I has Huntington’s. Persons II and III are being tested…results?

15. Crime Scenes and DNA Evidence Investigator at one of the crime scenes (above), Narborough, England (left) 0 • Many violent crimes go unsolved for lack of enough evidence • If biological fluids are left at a crime scene, DNA can be isolated from them • DNA fingerprinting determines with near certainty whether two samples of DNA are from the same individual

16. Blood from defendant’s clothes Defendant’s blood Victim’s blood Figure 12.12B 0 DNA fingerprinting can help solve crimes, paternity suits Figure 12.12A Q: Did he do it? Fingerprint (12E) activity and Discovery channel “Forensics” video

17. DNA Fingerprinting Activity • DNA Fingerprinting

18. The Human Genome Project : a major application of DNA technology 0 • Began in 1990: involved genetic and physical mapping of chromosomes and DNA sequencing • Data provide insight into development, evolution, and diseases • Most of the human genome does not consist of genes • The haploid human genome contains about 25,000 genes and a huge amount of noncoding DNA • noncoding DNA: repetitive nucleotide sequences (“junk DNA”) and transposons that can move about within the genome • repetitive sections found at centromere and at tips of chromosomes (telomeres) provide chromosome structure • * telomeres have protective function for chromosomes • * significant loss of telomeric DNA quickly leads to cell death. • * abnormally long telomeres are linked to cancer cell immortality

19. The science of genomics compares whole genomes 0 • The sequencing of many prokaryotic and eukaryotic genomes • Nonhuman genomes can be compared with the human genome

20. Chapter 15 Genetic Engineering • 15.1 – Selective Breeding • Selective Breeding • Hybridization • Inbreeding • Biotechnology • Bacterial Mutations • Polyploid Plants

21. Selective Breeding: Hybridization and Inbreeding Selective Breeding: takes advantage of naturally occurring variations and passes them to next generation ex) corn has been highly selected by native Americans for centuries and changed from a useless grass to the most productive food crop on the planet. 1. Hybridization: crossing of dissimilar individuals to get the best of both into the offspring ex: disease resistance of one plus the crop yield of the other 2. Inbreeding: the continued breeding of those with similar characteristics ex: dog breeds are inbred to keep gene pool constant for those particular traits unique to that “breed” **down side: because all are so similar, you increase the chance that 2 recessive alleles for a disease join. Now that disease stays in that gene pool and is tuned over in a high frequency. (ex: hip problems in labs, arthritis in golden retreivers)

22. Q: How can we increase variation in a species? A: Cause Mutations 1. Radiation and chemical exposure of bacteria * most mutations are harmful, but a few prove beneficial for a particular environment ex: oil-digesting bacteria ex: attempts to mutate bacteria to “eat” radioactive waste and render it stable ex: attempts to mutate bacteria to digest metals and clean the environment of industrial waste • Polyploidism (in plants) * use chemicals that don’t allow chromosomes to separate during meiosis get a 2N egg or 2N pollen (sperm) * result? 3N or 4N plant * new polyploid species are bigger and stronger than diploid relatives * ex: bananas and other vital crops

23. 15.2 Recombinant DNA • Southern Blot • PCR • Recombinant DNA • Plasmids • Transformation • Genetic Marker • Transgenic Organisms • Clone

24. PCR is used to amplify DNA sequences 0 (PCR)polymerase chain reaction • used to clone a small sample of DNA quickly • produces enough copies for analysis • used when DNA source is scant or impure • in a few hours, PCR yields 100 Billion copies of one gene PCRanimation Figure 12.14

25. Changing DNA • Early work = Griffith’s experiments on bacterial transformation (recall from chapter 10) • A cell takes in DNA from outside the cell and becomes a part of that organism’s genome

26. BACTERIAL PLASMIDS AND GENE CLONING 0 Plasmids are used to customize bacteria • Plasmids are extra rings of DNA outside the bacterial nucleoid • Researchers can insert desired genes into plasmids, creating recombinant DNA plasmids (rDNA) • The new plasmids are inserted into other bacteria • If the recombinant bacteria multiply into a clone, the foreign genes are also copied • The bacteria can also express the new gene and make the protein • Ex: insulin production real plasmid • Bacteria are used as: • copy machines (to clone genes) • factories (to make protein of inserted gene)

27. 0 Bas i c Process Figure 12.1

28. Plasmids and Genetic Markers Problem: DNA molecules inserted into host cells were not replicated: Solution:Use plasmids to introduce Plasmid – a piece of circular bacterial DNA Plasmids generally contain: a. a replication start signal (ori), restriction enzyme start site (EcoR1) genetic markers like antibiotic resistance genes (tetracycline and ampicillin)

29. Plasmids and Genetic Markers Recombination Process using Plasmids The same restriction enzyme is used to cut plasmid and DNA of interest The DNA of interest is joined to the plasmid using ligase Recombined DNA is inserted into the host cell The genetic marker (like antibiotic resistance) identifies the recombined DNA after bacterial growth

30. 0 Cloning a gene in a bacterial plasmid • Sometimes a genetic marker is used to ‘see’ if the bacteria has accepted the new DNA (a gene that is resistant to antibiotics, one that glows, etc.) Cloning animation Figure 12.3

32. Transgenic Organisms Transgenic – containing genes from other species Can be produced by insertion of recombinant DNA into the genome of host organism Transforming a Plant Cell Possible bc of universal genetic code Can increase food supply

33. Transgenic Animals: contain genes from other animals 0 • Genes from other organisms are inserted into their genomes • Involves in vitro fertilization and injection of desired gene directly into fertilized eggs • Engineered embryos are implanted into a surrogate mother • Ex: pigs with human cell lines for organ donation • Ex: chickens produce eggs with additional proteins Q : Is it ethical? What are the risks? What happens when a GM crops pass genes for pesticide and herbicide resistance to weeds??  superweeds that would be very difficult to destroy

34. Examples of Transgenic Organisms

35. To Clone or Not to Clone? 0 • A clone is an individual created by asexual reproduction • genetically identical to a single parent • Cloning has many benefits but evokes just as many concerns

36. Nuclear transplantation is used to clone animals 0 • * Reproductive cloning of nonhuman mammals is useful in research, agriculture, and medicine • * Therapeutic cloning produces stem cells which can perpetuate themselves in culture and give rise to specialized cells cloning stem cell research

37. Cloning Clone – A member of a population of genetically identical cells produced from a single cell Steps in nuclear transplantation cloning: Nucleus of an unfertilized egg is removed Egg cell is fused with a donor cell that contains a nucleus The egg and donor cell are fused using an electric shock Diploid egg develops into an embryo Embryo is implanted in the uterine wall of a foster mother. Animals cloned: frogs, sheep (Dolly 1997), cows, pigs, mice and cats

38. Yes, the jokes are FREE!!!!!

39. 15.3 Applications of Genetic Engineering • Health and Medicine • Gene Therapy • DNA Microarray • DNA Fingerprinting • Forensics

40. 15.3 Applications of Genetic Engineering Have you eaten genetically modified (GM) foods this week? GM Crops – transgenic plants that resist pests, herbicides, disease and result in increased yields. -Use of these crops is on the rise -Introduced in 1996 (soybean) -As of 2007 GM crops made up 92% of soybeans, 86 % of cotton and 80% of corn Examples: Roundup ready soybeans, Bt corn, tomatoes, rice, potatoes

41. GENETICALLY MODIFIED (GM) ORGANISMS • Recombinant DNA technology is producing new genetic varieties of plants and animals • Use Ti plasmid of Agrobacterium tumefaciens as the vector GM plant • ex: soybeans and cotton crops receive bacterial genes to make them resistant to herbicides and pests • ex: “golden rice” = rice with a few daffodil genes added. Rice plant can now make B-carotene, needed for vitamin A production in humans. Vitamin A deficiency (and resulting blindness) is a serious problem for ½ of the world who depend on rice as their staple food. Ti plasmid animation

42. 15.3 Applications of Genetic Engineering GM animals – engineered to increase production, nutritional benefit or product not typically associated with that animal. 30% of milk in US is coming from cows injected with bovine growth hormone (BGH) In 2008, US approved the sale of meat and milk from cloned animals.

43. 15.3 Applications of Genetic Engineering Examples of GM foods: Cows – BGH, increased milk output Pigs – leaner meat, omega 3 acids Salmon – GH, shorter time to market Goats – spider genes to manufacture silk, antibacterial goat milk

44. Recombinant cells and organisms can mass-produce gene products for medicinal and other purposes 0 1982: Humulin The first recombinant drug made by bacteria and approved by the FDA

45. Mass-Produced Gene Products cont’d • Bacteria with plasmid: get gene product in large quantity ex: insulin • S. cerevisiae yeast: eukaryotic cell with plasmids can produce eukaryotic proteins better ex: proteins for hepatitis B vaccine • Mammalian cells: can process large proteins better ex: Factor 8 (fight hemophilia), TPA (fight heart attacks) and EPO (fight anemia) • Whole organism: gene is added to genome and the gene product (protein) is then produced in the organism ex: human gene into cows to make milk with human protein ex: human gene into sheep to make milk with a blood protein to fight CF HepB vaccine animation

46. The Simpsons’ Background information: Homer got into a dispute at a local establishment. To avoid a standoff, Homer takes his family to his father’s farm to hide out. We join Homer and his family as they arrive at the farm. TOMACCO Explain, in detail, how this Simpsons’ clip relates to genetic engineering.

47. Gene Therapy • Gene Therapy – an absent or faulty gene is replaced by a normal, working gene. • The first attempted of a gene transfer to cure a disease occurred in 1990. • Scientist engineer a virus to carry the new gene into the target cells • Problem: need reliable ways to insert working genes in target cells and ensure DNA used does no harm.

48. Gene Therapy 0 • Is the alteration of an afflicted individual’s genes • Use a harmless recombinant virus as a vector (deliverer of needed gene) • Remove bone marrow cells and treat with recombinant virus • “infected” cells with injected gene are put back into patient. • Patient now has needed gene in bone marrow cells • May one day be used to treat both genetic diseases and non-genetic disorders. Unfortunately, progress is slow Figure 12.13

49. Technique used to study LOTS of genes at once and to understand their activity levels ssDNA spots are attached to a glass slide (spots contain different fragments) Colored tags are used to label the source of DNA EX. compare cancer genes with normal genes DNA Microarray

50. Southern Blot • Technique for finding specific DNA sequencesusing a labeled piece of nucleic acid as a probe