Presentation on theme: "Chapter 13 Gene Technology. DNA Technology DNA: – Can be used as evidence in a criminal case – Improve food crops – Determine if a person is carrying."— Presentation transcript:
DNA Technology DNA: – Can be used as evidence in a criminal case – Improve food crops – Determine if a person is carrying a genetic disease – To do research to treat and cure genetic diseases
DNA Identification Human genome: the complete genetic material in an individual There is only a 0.1 % variation from person to person About 98% of our genetic makeup does not code for any protein, these regions of DNA are called noncoding DNA Noncoding DNA comes in different lengths called length polymorphisms Differences in lengths of noncoding DNA and other variations account for many of the differences in DNA among individuals
Steps in DNA Identification 1.Copying DNA -Polymerase Chain Reactions (PCR) quickly produces many copies of DNA
Steps in DNA Identification 2. Cutting DNA – Restriction Enzymes: bacteria proteins that recognize specific DNA sequences and cut the DNA at the sequence
Steps in DNA Identification 3. Sorting DNA by size – Gel Electrophoresis: separates DNA fragments according to their size and charge (+ or -) – DNA Fingerprint: resulting pattern of DNA fragments
Steps in DNA Identification – Shorter fragments move fasters and farther than longer fragments – Negatively charged DNA moves towards the positive side of the gel electrophoresis tray – Gel is stained and can be transferred to a film or paper for analysis
Bioethics Warm-Up Would you want to know if you were genetically predisposed to a certain disorder (like heart disease or diabetes)? What if it was for a disorder that has no known treatment?
Checking for Understanding How are DNA fingerprints similar to real fingerprints? How are they different?
Steps in DNA Identification 4. Accuracy of DNA fingerprints – DNA Fingerprint: resulting pattern of DNA fragments – The odds that two people will share an identical DNA profile are approximately 1 in 100 billion The odds of being attacked by a shark in the United States are roughly 1 in 8 million
Recombinant DNA Genetic engineering: Process of altering the genetic material of cells or organisms to allow them to make new substances Recombinant DNA: DNA from two different organisms are joined – Ex: inserting a jellyfish gene that codes for green fluorescent protein into other species
Recombinant DNA Gene of interest: a segment of one species’ DNA that scientists wish to insert into another species’ DNA Plasmid: small rings of DNA found naturally in bacteria cells
Recombinant DNA http://www.youtube.com/watch?v=x2jUMG2 E-ic http://www.youtube.com/watch?v=x2jUMG2 E-ic
Bioethical Question Should a company be allowed to patent (and own the exclusive rights of) a genetically modified organism?
Genetic Engineering Medical applications: – Allows biologists to study how genes function
Gene Therapy Treats genetic disorders by introducing a gene into a patient’s cells Works best for disorders that result from the loss of a single protein Ex: cystic fibrosis is currently being worked on
Goal of most animal cloning is to alter the genome in a useful way – Ex: Cloning of goats so they secrete human blood clotting factors into milk – Ex: Cloning of pigs for organ transplants in humans
Vaccines DNA vaccines are made from the DNA of the pathogen, but does not have disease-causing capability Ex: AIDS, malaria, certain cancers
Agricultural Applications Making crops: – More tolerant to environment conditions – Resistant to herbicides – To increase food yields – Resistant to disease – Nutritional value greater
Ex: Golden Rice Created to provide people with Vitamin A Developed to help the very poor
Ex: Flavr Savr Tomato Created to prevent the softening of the tomato Made more resistant to rotting Could be “vine-ripened”
Ex: Glofish Inserted fluorescent gene from a jellyfish into zebrafish Sold as a pet
Ex: Roundup Ready Soybeans Soybeans that are resistant to Roundup herbicide Created to reduce the application of harmful herbicides
Ethical Issues Bioethics – study of ethical issues related to DNA technology Most scientists feel rigorous testing and safeguards should be in place for crop alteration
Ethical Issues Most scientists consider gene therapy unethical if it involves reproductive cells that would affect future generations Decisions about ethical issues are made by the involvement of the scientists and informed public
Bioethical Question Should we be able to insert non-human DNA into human DNA? Would this change what it means to be “human”? Should humans be able to alter our intelligence via genetic engineering?
Bioethical Question If there aren’t any risks associated with GM foods, should companies be required to label foods made with GMOs?