Download Genetic Engineering

Genetic
Engineering
the manipulation of living
organisms for human use
Chapter 13
Breeding strategies
• Selective breeding: only
certain individuals with certain
traits are selected to reproduce
• Inbreeding: crosses individuals
with similar traits
• Hybridization: crosses
individuals with different traits;
tend to be hardier and healthier
Manipulating DNA
• Genetic engineering: making changes in the
•
DNA code of an organism
Restriction enzymes: cut the DNA at specific
sites by recognizing certain DNA sequences
– produces more manageable pieces of DNA to
separate and analyze
• Gel electrophoresis: separates DNA fragments
through a gel using electricity; creates a “DNA
fingerprint”
– Identifying criminals
– Paternity (who is the father of the baby?)
Gel Electrophoresis
DNA fingerprinting
• method of DNA analysis which identifies
individuals by examining DNA fragments
• Steps
– sample of DNA is cut using restriction enzymes
– fragments are separated using electrophoresis to
create a pattern of bands (negatively-charged DNA
moves towards positive-end of apparatus)
– Shortest segments travel the furthest (easier to move
through gel)
Using DNA
• Recombinant DNA: the manipulation of
specific genes in the cells of living
organisms causing them to produce new
or unusual substances
• Polymerase Chain Reaction (PCR):
uses DNA polymerase to create thousands
of copies of a gene
Application of Gen. Eng.
• Transgenic Organisms
– Contain DNA from another species
– Example: insulin-producing bacteria
– 52% of soybeans, 25% of corn are
genetically-modified (“GMO”)
Application of Gen. Eng.
• Cloning
•
– Clone: member of a
population of
genetically identical
cells that are produced
from a single cell
– Somatic Cell Nuclear
Transfer
In 1997, Ian Wilmut
presented “Dolly”, the
first cloned sheep
• http://learn.genetics.utah.edu/
content/tech/cloning/whatisclo
ning/
Steps of Cloning
Human Genome Project
• An ongoing effort to analyze the human
DNA sequence
• Started in 1990, completed in 2000
• Different scientists studied random
fragments of DNA then combined their
data
• Humans have approximately 35,000 genes