Unraveling Genetics: From Selective Breeding to Genetic Engineering

1. DO all dogs come from wolves?

2. Selective Breeding • An organism (plant/animal) with desired traits are crossed (bred) so that the next generation will exhibit those traits • Takes time, energy, and several generations before the trait is common in a population • Purpose: increase the frequency of a desired allele

3. EX: Selective Breeding Over years of selective breeding What corn first looked like

4. Selective breeding of plant can increase productivity of food for humans • EX: cross a disease resistant plant with a plant that produces lots of fruits • What are you going to get?

5. Inbreeding • Mating between closely related individuals • Ensures offspring will be homozygous for desired traits • Negative- brings out harmful recessive alleles

6. IS THIS POSSIBLE?

7. Genetic Engineering • Faster and more reliable method than selective breeding • It is also referred to as Recombinant DNA

8. STOP

9. Applications of Genetic Engineering • Use recombinant bacteria to clean up Oil spills • Use it in medicine to treat disease, such as Dwarfism and Diabetes • Agriculture- made plants to be frost-resistant

10. Bt Corn Evolution Bt corn and bug genes • Do you eat GMO’s? • Would you eat GMO’s?

11. STOP

12. You’re going to write the following without guided notes

13. Genetic Engineering • How: Cut DNA (also know as cleaving) from one organism into small fragments • Then, they insert those fragments into a host organism of the same or different specie

14. Transgenic Organisms • Organisms that contain foreign DNA from Genetic Engineering • EX: tobacco plant that glows

15. Transgenic Organisms Plants and animals that can glow!

16. Transgenic Organismsare alsocalled Genetically Modified Organisms(GMO’s)

17. Steps to Recombinant DNA • 1) Isolate the foreign DNA fragment • 2) Attach DNA fragment to a “vehicle” called a Vector • 3) Transfer the vector into a host

18. 1. Isolate DNA • Cut (cleave) small pieces of DNA using a Restriction Enzyme • Restriction enzymes are bacterial proteins that cut DNA in a SPECIFIC nucleotide sequence, called a Recognition Site • There are 100’s of Restriction Enzyme

19. Example of Step 1 • EX: The section of Firefly DNA that codes for the light producing enzyme is cleaved (cut) using a Restriction Enzyme called EcoRI

20. Restriction enzyme Cut the Firefly DNA Sequence at AATT

21. Sticky Ends • Where Restriction Enzymes cut the DNA is called Sticky Ends • Sticky Ends WANT to join with DNA again, because part of it has become single stranded

22. Sticky ends

23. 2. Vectors • The DNA fragments that have been cut, need to be inserted into a Vector (vehicle) • Vector- a way that DNA from another species can be carried into the host cell • Vectors can be biological or mechanical

24. Vector Examples • Biological Vectors: Viruses and Plasmids • Plasmids are small rings of DNA found in a bacterial cell • Mechanical Vectors: Micropipette or tiny metal bullet

25. Micropipete

26. 2. Example of Vectors • The firefly’s light producing DNA is inserted into a Plasmid

27. Step 3: Transfer into a host • The recombined DNA is transferred into a bacterial cell (Bacteria = HOST) • The bacterial cell replicates up to 500 times per cell making copies of the recombinant DNA

28. Each copy that the bacterial cell makes of the recombinant DNA is called a Gene Clone • Rejoining the DNA Fragments (Firefly’s glow code + the Plasmid’s DNA) is called Gene Splicing

29. 3 Steps to recombinant DNA • 1. Isolate DNA • 2. Cut DNA and combine with a plasmid • 3. Transfer into a host • animal pharm

30. STOP

32. DNA fingerprinting- patterns of bands seen on the gel electrophoresis. • Unique to each individual • Used to: • Solve crimes • Unsolved mysteries • Determine Family Relationships

33. Gel Electrophoresis • It is used to separate DNA Fragments • The gel used has small pores

34. 1. Restriction Enzymes cut DNA into small fragments • 2. DNA fragments are then poured into wells on the gel

35. 3. An electric current is hooked up to the gel, and moves the DNA across the gel • 4. DNA is slightly negative and will move towards the positive pole • 5. The smallest pieces will move the fastest

36. 6. A dye is added, and the result will be bands of DNA

37. Medicine • Cures found in DNA codes • Genetic techniques developed: • Gene therapy • Improve and develop vaccines • Diagnose disorders

38. Gene Therapy • Fastest growing areas in genetic engineering • Gene therapy- thechangingofgenesthat cause a genetic disorder or controlling the symptoms of a disorder. Example: cystic fibrosis

39. STOP

40. cloning your pet

41. Dolly: First Mammal Cloned • Dolly was born Feb. 1997 • First mammal cloned from an adult cell

42. What is a clone? • A clone is GENETICALLY IDENTICAL to it’s parent cell

43. 3 steps to clone: a sheep for each step • 1. REMOVE SOMATIC (BODY) CELL NUCLEUS FROM AN ADULT SHEEP • 2. REMOVE AN EGG CELL FROM AN ADULT SHEEP AND REMOVE THE NUCLEUS • 3. COMBINE THE BODY CELL AND THE EGG CELL, AND IMPLANT IT IN A SURROGATE

44. STEP # 1: REMOVE SOMATIC CELL • A body cell(AKA SOMATIC cell) from the mammary gland of a female sheep is taken • Take out the somatic cell nucleus • The body cell will determine what the organism will look like because we will keep its nucleus

45. STEP # 2: SHEEP # 2 • An Egg cell from adifferent Female sheep & remove its nucleus • Body cell + Egg cell = an embryo in a test tube

46. step # 3: sheep # 3 • Embryo is implanted in a surrogate mother sheep will the baby sheep that is born look like its surrogate?

47. what will the baby sheep look like if the somatic cell is from a white faced sheep?...

48. Cloning

49. The Human Genome Project (HGP) • The Human Genome Project (HGP) • Has mapped and sequenced the entire human genome • It was started in 1990 • First draft was done in 2000

50. Genes are placed on a Linkage Map • Linkage Map - a genetic map that shows the location of genes on chromosomes • Why? It’s faster than using a pedigree chart • Scientists are able to look for “genetic markers” to track inheritance patterns