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GENETIC TECHNOLOGY. GENETIC MUTATIONS. GENE MUTATIONS Change/mistake with individual gene Point Mutation – 1 amino acid is changed. Frameshift Mutation – an amino acid is added or deleted. GENETIC MUTATIONS. CHROMOSOMAL MUTATIONS Mistakes affect the entire chromosome
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GENETIC MUTATIONS • GENE MUTATIONS • Change/mistake with individual gene • Point Mutation – 1 amino acid is changed • Frameshift Mutation – an amino acid is added or deleted
GENETIC MUTATIONS • CHROMOSOMAL MUTATIONS • Mistakes affect the entire chromosome • Deletion: lose part of chromosome • Duplication: gain extra parts on a chromosome
GENETIC MUTATIONS • Inversion: rearrangement of the chromosome • Translocation: genes are rearranged btw 2 different chromosomes
GENETIC MUTATIONS • Nondisjunction: chromosomes do NOT separate during meiosis results in polyploidy (too many chromosomes) • Cause of many different genetic diseases • Down’s, Klinefelter, Turner’s, Triple X, XYY
DIAGNOSING GENETIC DISEASES • GENETIC COUNSELORS • Research family history to determine parents’ risk of passing genetic disorders to their children • Typically used by couples with family history of genetic disorders
DIAGNOSING GENETIC DISEASES • GENETIC TESTING • Carrier Recognition – parents can be tested to see if carry genes for genetic disorder • (Tay-Sachs, cystic fibrosis, sickle-cell anemia) • Fetal Testing – test unborn child for genetic disorders • Remove fetal tissue • Allow cells to multiply in the lab • Magnify & photograph chromosome spread • Create a karyotype – map of chromosomes
DIAGNOSING GENETIC DISEASES • Types of Fetal Tests: • Amniocentesis (15-20 wks) – remove amniotic fluid from mother • Fluid tested for chemical indicators or used create karyotype • CVS - Chorionic Villus Sampling (8-10 wks) • Remove tissue from placenta – more immediate results • Ultrasound – looks for major structural abnormalities • Fetoscopy – insert fiber optic scope into uterus to examine fetus for major abnormalities
DNA FINGERPRINTS • DNA can be collected from any living tissue • (blood, skin, hair, urine, semen, sweat or tears) • Gel Electrophoresis • DNA sample is inserted into a “gel” • An electric current is passed through the gel • Shorter strands move farther down the gel as pieces of DNA separate & show up as bands • Gel is stained to make the bands more visible • Samples are compared to find a match
Human Genome Project • Map all the genes on the 46 human chromosomes • Information has led to many advances in the fields of medicine, agriculture, bio-engineering
GE – WHAT IS IT? • Removing genes from one organism and inserting them in another
GE – HOW DO THEY DO IT? RESTRICTION ENZYMES • Naturally occur in bacteria – used cut up foreign DNA (form of protection) • Cut DNA fragments are called “sticky ends” • S. ends of DNA fragments can be joined in a lab to produce recombinant DNA (mix of DNA)
GE – WHAT CAN IT DO? PROS • Disease resistant crops • New vaccines & medications (insulin) • Bigger livestock more meat, milk, wool etc. CONS • Unpredictable technology is new & no guarentee that products free of side affects • $$ companies patent genes & demand high prices
GENE THERAPY • Replace defective genes w/ normal or functional genes • When cells reproduce normal gene will also be replicated • Most suitable for single gene mutations • Enzyme deficiencies
SOMATIC CELL THERAPY • Somatic cells = body cells • Mutated cells removed • Corrected gene inserted • “New” cells returned • Affects only the individual receiving treatment • Temporary cure – cells die off
STEM CELL THERAPY • Stem cell = basis all future cells • Found embryo, chord blood & bone marrow • May provide broader, more long-lasting treatment • Not currently safe or 100% effective
GERM CELL THERAPY • Germ cells = gametes • Replace or remove defective genes in sperm/egg cells prior to fertilization • Affect future generations • Permanent solution • Successful in mice & primates • Social & Ethical Issues • Are humans next? • Who should have access to this technology? • Are we playing God? • If we can fix disorders, what else could we fix? • Where do we draw the line – what is too much?