Genetic Genetic Engineering Engineering

STS Biology STS Biology Unit 4 Unit 4

GeneticsGeneticsMrs. SteinMrs. Stein

What is Genetic What is Genetic Engineering?Engineering?

Manipulating DNA for practical Manipulating DNA for practical purposes:purposes:– DNA sequencing and the Human DNA sequencing and the Human

GenomeGenome– Transgenic organisms have many Transgenic organisms have many

applications in agricultureapplications in agriculture– DNA fingerprinting used in DNA fingerprinting used in

forensicsforensics

Genetic Engineering Genetic Engineering Tools: PCRTools: PCR

Polymerase chain reaction (PCR) uses DNA polymerase to make many copies of DNA

Gives scientists enough DNA to work with!

Genetic Engineering Genetic Engineering Tools: Restriction Tools: Restriction

EnzymesEnzymes Proteins which Proteins which

recognize and cut recognize and cut specificspecific base base sequencessequences in DNA in DNA

Results in fragments Results in fragments of DNA with of DNA with “sticky “sticky ends”ends”

First step in many First step in many DNA manipulationsDNA manipulations

PlasmidsPlasmids Plasmids – circular DNA Plasmids – circular DNA

molecules in many bacteriamolecules in many bacteria

Plasmid use in genetic Plasmid use in genetic engineering engineering

Recombinant DNA and Recombinant DNA and PlasmidsPlasmids

Genes are “spliced” into plasmidsGenes are “spliced” into plasmids Recombinant DNARecombinant DNA –contains DNA –contains DNA

from different sourcesfrom different sources Plasmids containing the target gene Plasmids containing the target gene

are reproduced (cloned) inside are reproduced (cloned) inside bacteriabacteria

Used to make various proteins:Used to make various proteins:– insulin, human growth hormone, pest insulin, human growth hormone, pest

resistance proteins in plantsresistance proteins in plants

Gel ElectrophoresisGel Electrophoresis

DNA fragments are placed in wells of the gel

DNA digested by restriction enzymes

Gel

DNA is negatively charged so it will migrate to the positive size

Power source

Longer DNA fragments

Shorter DNA fragments

DNA DNA FingerprintingFingerprinting

Analysis of gel Analysis of gel electrophoresis to electrophoresis to compare the compare the genomes of genomes of organismsorganisms

Used in crime Used in crime investigations and investigations and paternity testspaternity tests

Whose kids are Whose kids are these???these???

Using the gel, Using the gel, determine:determine:– Which child/children Which child/children

are the offspring of are the offspring of both mom and dad?both mom and dad?

– Which child/children Which child/children are the dad’s child from are the dad’s child from another marriage?another marriage?

– Which child/children Which child/children are the dad’s child from are the dad’s child from another marriage?another marriage?

– Which child/children Which child/children are adopted?are adopted?

Transgenic Transgenic OrganismsOrganisms

Organisms containing Organisms containing genes from other speciesgenes from other species

Transgenic bacteria Transgenic bacteria produce growth hormoneproduce growth hormone

Transgenic plants and Transgenic plants and animals improving animals improving agricultureagriculture

CloningCloning

Making a Making a genetically genetically identical organismidentical organism

Potential to use Potential to use cloning to treat a cloning to treat a variety of diseasevariety of disease

How was Dolly the sheep How was Dolly the sheep made?made?

Donor Nucleus

Cells are fused

Nucleus is removed from the egg cell

Egg CellFused Cell

Embryo

Foster MotherCloned Lamb