DNA Technology

DNA Extraction Chemical treatments cause cells and nuclei to burst The DNA is inherently sticky, and can be pulled out of the mixture This is called “spooling” DNA

“Spooled” DNA

Cutting DNA Restriction enzymes cut DNA at specific sequences Useful to divide DNA into manageable fragments

Electrophoresis DNA can be separated based on size due to 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

Cloning Clone- a member of a group of genetically identical cells May be produced by asexual reproduction (mitosis)

Cloning organisms A body cell from one organism and an egg cell from another are fused The resulting cell divides like a normal embryo

Cloning “Dolly”

Human Genome Project

Human Genome Project Started in 1990 Research effort to sequence all of our DNA (46 chromosomes) Over 3.3 billion nucleotides Mapping every gene location (loci) Conducted by scientists around the world

HGP Insights Only 2% of human genome codes for proteins (exons) Other 98% (introns) are non-coding Only about 20,000 to 25,000 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 About ½ of genome comes from transposons (pieces of DNA that move to different locations on chromosomes)

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 …

Activity Complete Problem Solving Lab on page 353

Cutting DNA Restriction enzymes cut DNA at specific sequences Useful to divide DNA into manageable fragments

Recombinant DNA Combining DNA from two different organisms Placed in transgenic organisms, living things that contain recombinant DNA

How it happens: Cut plasmid (circular DNA in bacteria) with restriction enzyme Cut gene of interest with restriction enzyme Ligase “glues” together gene of interest with plasmid Bacteria (now transgenic organism) produces protein coded by gene of interest

Benefits of Genetic Engineering

Gene Therapy Process by which a person is given new DNA from a donor for the purpose of curing a disease

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

Biotechnology Provides: Improved food products Medical advances An enhanced environment

Herbicide Resistant Crops + CP4 EPSPS = Roundup gene Ready Soybeans: Roundup Ready Corn: Roundup Ready, Liberty Link Cotton: BXN, Roundup Ready Canola: Liberty Link, Roundup Ready

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

Biotechnology Breakthroughs Potatoes with higher solid content Garlic that lowers cholesterol Fruits and vegetables that reduce risks of cancer and heart disease

Environmental Benefits Reduced pesticide use Lower energy requirements Cleaner water Less soil erosion

Activity Complete MINI-lab on page 343 Complete Problem-Solving Lab on page 347