Transcript A27-Biotechnology and Ethics

Biotechnology & Genethics
What can we do with
Biotechnology?
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Genetic Screening & testing
In vitro fertilization
Gene therapy & new treatments
Cloning
DNA fingerprinting
Paternity testing
Genetically modified crops
The Human Genome Project
• Completed in 2003
• Scientists all over the world worked to
sequence the human genome and trace traits
to specific chromosomes.
• This work has made it possible to pinpoint
the location of many genetic disorders and
diseases in our DNA.
• See poster
Genetic Screening & Testing
• Before a baby is born, parents can know if
there is a chance of it having a disease or
disorder.
– Premarital testing: couple gets genetic tests
– Prenatal testing: Amniocentesis, Ultrasound, …
– Neonatal testing & Newborn testing: PKU,
Cystic Fibrosis, Tay-Sachs, & Sickle Cell
In vitro Fertilization
• Couples who have trouble conceiving can
seek this as an option. The egg is fertilized
by sperm in a petri dish, and verified by a
scientist ex utero, in addition to being
screened for diseases and disorders.
Gene Therapy & New Treatment
• Gene therapy- body cells and tissues are
injected with functioning copies of a gene to
replace defective genes.
• Stem Cell Research- embryonic stem cells
could be transplanted to repair human
tissues and cure diseases. Stem cells have
the ability to differentiate into any type of
body cell.
Cloning
• Bacterial cloning of a gene- ex. Insulin
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Gene of interest is isolated from human DNA
Bacterial DNA is cut open
Gene is inserted into bacterial DNA
Bacteria reproduce and gene is cloned
Bacteria go through protein synthesis and make
protein from new gene
– New protein can be harvested from bacteria
http://www.dnai.org/text/mediashowcase/index2.
html?id=558
Cloning
• Whole Organism- ex. Dolly in 1997
– Nucleus removed from a sheep’s somatic cell
– Nucleus inserted into empty egg cell (nucleus
was removed from this also)
– Egg cell acts like a normal egg cell, and
develops into an embryo
– Embryo inserted into surrogate sheep
– Dolly born months later!
Genetic Engineering
• Selective Breeding- animals with the best traits are
breeded
• Genetically modified organisms (GMOs):
– Pest or herbicide resistant crops
– Heartier, more flavorful, or longer lasting crops
– Plants or animals that produce more offspring
– Accidentally can create resistant species (ex. MRSA)
http://nortonbooks.com/college/biology/animations/ch15p
03.htm
DNA Fingerprinting
• Suspects’ DNA and DNA recovered from
crime scene can be cut by restriction
enzymes, and sorted by fragment size to see
if they match (through a process called gel
electrophoresis). Can also be used in
paternity testing.
http://learn.genetics.utah.edu/content/labs/gel/gel_electrophoresis.swf
Just because we can, should we?
• Many ethical questions have come up
concerning biotechnology. For ex.:
– How much genetic screening & selecting
should we allow?
– Is it right to create new or modified species and
“play God”?
– Should stem cell research be allowed?