DNA TECHNOLOGY

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: 6.1 billion

Odds of being struck by lightning in the U.S.: 2.8 million to 1

Odds of winning the Georgia’s Big Game lottery: 76 million to 1

Odds of getting killed driving to the gas station to buy a lottery ticket 4.5 million to 1

Odds of seeing 3 albino deer at the same time: 85 million to 1

Odds of having quintuplets: 85 million to 1

Odds of being struck by a meteorite: 10 trillion to 1

Biotechnology, defined broadly, is the engineering of organisms for useful purposes.

Often, biotechnology involves the creation of hybrid genes and their introduction into organisms in which some or all of the gene is not normally present.

Biotechnology

Biotechnology, defined broadly, is the engineering of organisms for useful purposes.

Often, biotechnology involves the creation of hybrid genes and their introduction into organisms in which some or all of the gene is not normally present.

Recombinant DNA is DNA in which genes from 2 different sources are linked.

Fourteen month-old genetically engineered (“biotech”) salmon (left) and standard salmon (right).

Manipulating Genes

DNA Technology can be used to:*cure diseases*to treat genetic disorders*to improve food crops*and to improve the lives of humans

Biotechnology Tools

Restriction Enzymes- used to isolate a specific gene

Cloning Vectors- a carrier that is used to clone a gene and transfer it from one organism to another. Example: Plasmid

Plasmids are Used to Replicate a Recombinant DNA

*Plasmids are small circles of DNA found in bacteria.

*Plasmids replicate independently of the bacterial chromosome.

*Replication often produces 50-100 copies of a recombinant plasmid in each cell.

*Pieces of foreign DNA can be added within a plasmid to create a recombinant plasmid.

Restriction Enzymes are Enzymes That Cut DNA Only at Specific Sequences

The enzyme EcoRI cutting DNA at its recognition sequence

Different restriction enzymes have different recognition sequences.

This makes it possible to create a wide variety of different gene fragments.

Restriction enzyme animation

Forming Recombinant DNA using Restriction Enzymes:

Harnessing the Power of Recombinant DNA Technology – Human Insulin Production by Bacteria

Human Insulin Production by Bacteria

6) join the plasmid and human fragment

and cut with a restriction enzyme

Human Insulin Production by Bacteria

Mix the recombinant plasmid with bacteria.

Route to the Production by Bacteria of Human Insulin

A fermentor used to grow recombinant bacteria.This is the step when gene cloning takes place.

The single recombinant plasmid replicates within a cell.

Then the single cell with many recombinant plasmids produces trillions of like cells with recombinant plasmid – and the human insulin gene.

One cell with the recombinant plasmid

Route to the Production by Bacteria of Human Insulin

The final steps are to collect the bacteria, break open the cells, and purify the insulin protein expressed from the recombinant human insulin gene.

Bacterial plasmids in gene cloning

DNA Technology Tools….

Polymerase Chain Reaction (DNA copying)

Gel Electrophoresis DNA Fingerprinting Cloning

Copying DNA Polymerase Chain Reaction Also called PCR A method of making many copies of a piece

of DNA

Steps in Copying DNA

• A DNA molecule is placed in a small test tube

• DNA polymerase that can work at high temps is added

Steps in Copying DNA

The DNA is heated to separate the two strands

Primers, short pieces of DNA complementary to the ends of the molecule to be copied, are added

Copying DNA

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

PCR

Large amounts of DNA can be made from a small starting

sample

Electrophoresis DNA can be separated

based on size and charge

The phosphate groups are negatively charged

DNA is placed in a gel and electricity is run through

Electrophoresis

Negative DNA moves toward the positive end

Smaller fragments move farther and faster

Electrophoresis

DNA FingerprintingDNA is now a powerful tool in identification.

Based on the fact that the amount of "junk DNA" differs uniquely between individuals.

Structural genes are often separated by large regions of repeating basepairs.

The number of these repeats is unique to an individual.Therefore when DNA from a person is cut with a restriction enzyme, the length of the fragments will be unique to an individual.

DNA Fingerprinting Continued…

This will therefore produce a unique banding pattern following a gel electrophoresis.

This test is highly accurate, and the probability of another individual possessing an identical banding pattern is estimated as around 1:14,000,000,000.

DNA Fingerprinting

DNA Fingerprint

EV shows the DNA at a crime scene. Samples 1-5 were taken and analyzed from suspects. Based on this evidence, which suspect is guilty?

Cloning Cloning is the process of

making a genetically identical organism through nonsexual means. It has been used for many years to produce plants (even growing a plant from a cutting is a type of cloning). Animal cloning has been the subject of scientific experiments for years, but garnered little attention until the birth of the first cloned mammal in 1997, a sheep named Dolly. Since Dolly, several scientists have cloned other animals, including cows and mice. The recent success in cloning animals has sparked fierce debates among scientists, politicians and the general public about the use and morality of cloning plants, animals and possibly humans

Dolly, the first mammal clone

This shows how a common type of reproductive

cloning works:

Dolly the Sheep

Dolly died in 2003. This was due to lung disease and crippling arthritis. Most sheep can live 11-12 years. Dolly was 6.5 years old.

Human Genome Project

Started in 1990-finished in 2003

Research effort to sequence all of our DNA (46 chromosomes)

Over 3.3 billion nucleotides in roughly 26,000 genes

Mapping every gene location (loci)

Conducted by scientists around the world

HGP Insights…what they learned

Only 2% of human genome codes for proteins (exons)

Other 98% (introns) are non-coding

Only about 26,000 genes (expected 100,000)

Proteome – organism’s complete set of proteins

About 8 million single nucleotide polymorphisms (SNP) – places where humans differ by a single nucleotide

Benefits of Human Genome Project

Improvements in medical prevention of disease, gene therapies, diagnosis techniques …

Production of useful protein products for use in medicine, agriculture, bioremediation and pharmaceutical industries.

Improved bioinformatics – using computers to help in DNA sequencing …

Gene Therapy

Gene therapy can be used to treat some genetic disorders. It is utilized when a a defective “unhealthy” gene is replaced with normal “healthy” gene. Here are some diseases that gene therapy may help with more research:

Cystic fibrosis Hemophilia Lung Cancer AIDS Ovarian Cancer Brain tumors

Example of gene therapy

1. Insert DNA version of normal allele into virus.

2. Let virus infect bone marrow cellsthat have been removed from thepatient and cultured.

3. Viral DNA carrying the normalallele inserted into chromosome.

Insert a gene into an inactivated or nonvirulent virus and use the virus's infective capabilities to carry the desired gene into the patient's cells.

What factors have kept gene therapy from becoming an effective treatment for genetic

disease?

Immune response Problems with viral vectors Multigene disorders

BiotechnologyBiotechnology

The use of gene science to create new products from plants and animals

The use of gene science to create new products from plants and animals

Biotechnology Provides:

Improved food productsMedical advances

Biotechnology Breakthroughs….

Insulin (1982) First commercial biotech product Reliable, inexpensive source of insulin

Rice Enriched with beta-carotene and iron

Bananas Containing edible hepatitis vaccine

Potatoes with higher solid content Garlic that lowers cholesterol Fruits and vegetables that reduce risks of

cancer and heart disease

Herbicide Resistant Crops

Soybeans: Roundup Ready Corn: Roundup Ready, Liberty

Link Cotton: BXN, Roundup Ready Canola: Liberty Link, Roundup

Ready

+ CP4 EPSPS = Roundup gene Ready