Biotechnology Kraj Watson and Crick 1953 Won the
Biotechnology Kraj
Watson and Crick 1953 • Won the Nobel Prize for discovering that the structure of DNA is a double helix.
Rosalind Franklin • Her x-ray photographs of DNA led to Watson and Crick discovering the double helix.
Selective Breeding Low Tech • Selecting which organisms to breed in order to get offspring with the desired traits. Done for hundreds of years! • It takes advantage of naturally occurring genetic • variation in plants, animals, and other organisms • Examples: • Purebred dogs (all dalmations have spots) • Milk cows bred for high milk production • Corn selected for highest yields, etc
DNA Extraction Beginning Higher Tech • Chemical treatments cause cells and nuclei to burst • The DNA is inherently sticky, sticky and can be pulled out of the mixture • This is called “spooling” DNA 5
“Spooled” DNA 6
Herbert Boyer & Stanley Cohen • Herbert Boyer, Stanley Cohen In 1973, Stanely Cohen and Herbert Boyer, invented the technique of DNA cloning (using bacterium), which allowed genes to be transplanted between different biological species. Their discovery signaled the birth of genetic engineering.
Stanley Cohen (on the left) and Herbert Boyer (on the right) They demonstrated that the gene for frogribosomal. RNA could be transferred into bacterial cells E. coli and expressed by them.
Transgenic Organisms q. Organisms that have had genes from other organisms inserted into their genome. q. In frog and bacterium experiments…. q The bacteria is a transgenic organism. q. Plasmid used to transfer the DNA from the frog to the bacteria and restriction enzymes used to cut the frog DNA into smaller fragments.
Plasmids Circular DNA frequently found naturally in bacterial cells. Used in recombinant DNA to transfer genes between cells.
Cutting DNA • Restriction enzymes (aka endonucleases) cut DNA at specific nucelotides. • Useful to divide DNA into manageable fragments 11
The process of genetic engineering
The outcomes of genetic engineering
DNA Inserted into a cell
Recombinant DNA Technology • Genetically modified food • Production of human proteins to treat disease Genetically engineered dna made by recombining fragments of dna from different organisms Chapter 1: Human Heredity by Cummings Thompson Learning Brooks/ Cole
Gene Therapy • Gene therapy is the insertion of genes into an individual's cells to treat a disease. Replacing bad alleles. • A virus is used which replicates by inserting its genes into the host cell's genome. Virus not the only technique. • Examples: Cystic fibrosis, Huntington’s Disease, Hemophilia, Sickle Cell Anemia, Muscular Dystrophy – Single Cell mutations Currently in Research.
Electrophoresis • DNA is separated based on size and charge • Restriction Enzymes used to cut the DNA into manageable fragments. • DNA is placed in a gel and electricity is run through 17
Electrophoresis • Negative DNA moves toward the positive end • Smaller fragments move farther and faster 18
Electrophoresis 19
DNA Fingerprinting • The chemical structure of everyone's DNA is the same. The only difference between people is the order of the base pairs. There are so many millions of base pairs in each person's DNA that every person has a different sequence. • Can be used in forensic science and to show relations in families.
DNA Fingerprinting Process • Uses electrophoresis, Sothern Blot (transfers to special paper), and radioactive elements to identify repeating base pairs.
DNA Fingerprinting • A given person's VNTRs come from the genetic information donated by his or her parents; he or she could have VNTRs inherited from his or her mother or father, or a combination, but never a VNTR either of his or her parents do not have. • Variable Number Tandem Repeats (VNTRs or RFLP
Mrs. Nguyen [blue], Mr. Nguyen [yellow], and their four children: D 1 (the Nguyens' biological daughter), D 2 (Mr. Nguyen's stepdaughter, child of Mrs. Nguyen and her former husband [red]), S 1 (the Nguyens' biological son), and S 2 (the Nguyens' adopted son, not biologically related
Forensics
Paternity
Who are the parents?
Cloning • Clone a member of a group of genetically identical cells • Example Dolly 27
Cloning organisms • A body cell from one organism and an egg cell from another are fused • The resulting cell divides like a normal embryo • The offspring is genetically identical to the mother. 28
Cloning “Dolly” July 5, 1996 Birth Scientist- Ian Wilmut Scotland 29
Cloning He. La Cells • Henrietta Lacks’ cancer cells were the source of the He. La cell line, one of the most important cell lines in medical research. Taken from a tumor biopsied at Johns Hopkins Hospital in 1951. No consent was obtained and no compensation paid. –Medical Ethics
He. La Cells Have Helped Science • • • • Develop virology—field of biology study of viruses Develop methods of freezing cells for storage Develop standardized methods for culturing cells Develop the first vaccine for polio Develop methods for accurately determining the number of chromosomes in cells— beneficial for cancer research Used to study effects of radiation Used to study effects of deep sea pressure Used to test safety of cosmetics and pharmaceuticals—replacing lab animals Used in research on HIV (human immunodeficiency virus), the most common sexually transmitted disease—to help with developing treatments for AIDS (acquired immunodeficiency syndrome) Used in research on what causes aging Used in studying the effects of salmonella and tuberculosis Used to determined that HPV (human papilloma virus) causes cancer Used to help develop treatments for Parkinson’s disease, influenza, leukemia, and hemophilia. From The Life of Henrietta Lacks, http: //www. thinksciencenow. com
Human Genome Project • Started in 1990 Completed 2003 • 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 32
Health Care • Microarray – Screens genome • 10 million children and adults in U. S. suffer from a genetic disorder • Develop new treatments Fig. 1. 11 Chapter 1: Human Heredity by Cummings Thompson Learning Brooks/ Cole
Biotechnology Breakthroughs • Insulin (1982) – First commercial biotech product – Reliable, inexpensive source of insulin • Rice – Enriched with beta-carotene and iron • Bananas – Containing edible hepatitis 35 vaccine
Biotechnology Breakthroughs • Potatoes with higher solid content • Garlic that lowers cholesterol • Fruits and vegetables that reduce risks of cancer and heart disease 36
Controversies §Avoid accidental release § Genetically modified crops must be safe for consumption and for the environment § Who will have access to an individual's genetic information? §The morality and ethics involved with the research. i. e. using animals and humans.
Part 1: It takes a Lickin’ The Crime On the evening of November 1, at approximately 8: 15 p. m. , Jimmy Sweet entered his bedroom, walked over to his desk, and sat down at his computer. While reaching for the computer's switch he noticed, out of the corner of his eye, that one of the items on a typically well-organized shelf was out of place.
• Jimmy shot across the room for a closer examination. Sure enough, the object in question had indeed been disturbed. The object had been sealed in an air-tight package. The package was now ripped open. The object was still inside, but it was no longer in its original condition. In Jimmy's eyes, it was now worthless.
• Jimmy pulled out what had been his mostvalued possession—his holographic NOVA lollipop. The confectionery treat was now a sticky mess. Someone had obviously indulged him- or herself in its sugary molecules. The lollipop's holographic image had been licked away.
• The Suspects The prime suspects in this case are Jimmy's seven sisters: Candy, Cookie, Sugar, Lolly, Honey, Brandee, and Carmela. Each one of these sisters is a notorious candy lover and is easily capable of committing this crime of confection. The suspects have been detained. DNA fingerprints of each are available.
Crime Lab • http: //www. pbs. org/wgbh/nova/sheppard/la bwave. html
http: //www. pbs. org/wgbh/nova/s heppard/lab 02. html
Review • What is DNA? And What is a Protein? • http: //learn. genetics. utah. edu/content/begin/ tour/ • What makes a firefly glow? • http: //learn. genetics. utah. edu/content/begin/ dna/firefly/
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