DNA Technology Human Genome Project - established to determine DNA sequence of humans. - useful in locating genes and curing disorders. Example Gene Therapy- replacing faulty gene with the correct gene. - accomplished by using viruses to deliver genes into cells. - currently experimental

Gene Therapy Bone Marrow Cell Nucleus Normal Gene Chromosomes Engineered Virus

Recombinant Technology rDNA is DNA with 2 or more sources Bacteria are used to copy DNA and make desired proteins Identify gene of interest and cut it out insert new gene into a plasmid insert plasmid into bacteria Vector – plasmid carrying new gene into host bacteria can express new gene or make copies of inserted DNA

insert “gene we want” into plasmid... “glue” together Recombinant Plasmid Plasmids used to insert new genes into bacteria cut DNA gene we want like what? …insulin …HGH …lactase cut plasmid DNA Cut DNA? DNA scissors? ligase insert “gene we want” into plasmid... “glue” together recombinant plasmid

Grow bacteria…make more transformed bacteria gene from other organism + recombinant plasmid vector plasmid grow bacteria harvest (purify) protein

Transgenics – organisms with foreign DNA Genetically modified organisms (GMO) enabling plants to produce new proteins Protect crops from insects: BT corn corn produces a bacterial toxin that kills corn borer (caterpillar pest of corn) Extend growing season: fishberries strawberries with an anti-freezing gene from flounder Improve quality of food: golden rice rice producing vitamin A improves nutritional value For example, a transgenic rice plant has been developed that produces yellow grains containing beta-carotene. Humans use beta-carotene to make vitamin A. Currently, 70% of children under the age of 5 in Southeast Asia are deficient in vitamin A, leading to vision impairment and increased disease rates.

Genetic Engineering Done 2 ways: 1. Selective Breeding - allows desired traits to breed together. Example A. Hybridization - crossing organisms with different traits - helps bring out the best traits B. Inbreeding (true-breeding) - crossing organism with similar traits - maintains the desired trait

Dog Breeds(selective breeding)

Polymerase Chain Reaction Also called PCR 2. DNA Manipulation - the copying, cutting, identifying, and transplanting of DNA Copying DNA Polymerase Chain Reaction Also called PCR A method of making many copies of a piece of DNA 9 9

Steps in Copying DNA A DNA molecule is placed in a small test tube DNA polymerase that works at high temp’s is added 10 10

Steps in Copying DNA The DNA is heated to separate the two strands Primers, short pieces of complementary DNA, are added 11 11

Copying DNA The tube is cooled, and DNA polymerase adds new bases to the separated strands 12 12

Large amounts of DNA can be made from a small starting sample PCR Large amounts of DNA can be made from a small starting sample 13 13

Gel Electrophoresis - process of separating DNA fragments for identification STEPS 1. DNA Extraction - DNA pulled out by cell fractionation in a centrifuge. 2. DNA cut into fragments - Restrictive Enzymes cut DNA at specific locations. * DNA is too large to analyze all together

Use of Restriction Enzymes Restriction enzyme cuts the DNA into fragments.

3. DNA Analysis a. Fragments placed in a porous gel. b. Electric current is applied to gel. - opposite sides become (+) & (-) c. (-) charged DNA moves towards (+) end of gel. d. Short fragments move farther than long fragments leaving bands. e. Position of bands is specific to each person.

Gel Electrophoresis

DNA Fingerprints

Uses of Genetic Technology 1. DNA Fingerprinting - DNA samples from blood, hair, etc. are identified by gel electrophoresis. - used to solve crimes by comparing DNA from a crime scene with suspect’s DNA.

2. Transgenic Organisms - implanting genes from one species into another species. Example a. Microorganisms - bacteria can produce human insulin using human genes. b. Animals - mice are given human genes and studied. - farm animals are given genes to produce extra growth hormones.

c. Plants - genes for natural insecticides can be placed into crop plants. - genes that make vitamins can be added to plants. - Genetically Modified Organism - organism w/ altered genes to produce a desired affect. Tobacco plant with a lightning bug gene.

-creating a genetically identical organism from a single body cell. 3. Cloning -creating a genetically identical organism from a single body cell. (+) useful in producing transgenic organisms and saving endangered species (-) many cloned animals suffer from defects Body Cell Egg Cell Surrogate Mom Clone