Download Manipulating the Genome & Gene Therapy 6.4 6.5

Manipulating the Genome
6.4
Recombinant DNA
• genetic information
from different
organisms can be
combined, forming
recombinant DNA
Restriction Enzymes
GMOs
• bacteria that produce human insulin
• tomatoes with fish antifreeze gene
• goats that produce spider silk in their
milk
• Bt corn with bacterial gene that
produces insecticide
Gene Therapy
6.5
Gene Therapy
• attempt to “fix” a genetic defect through
the addition of normal gene or repair of
the defective gene
• use of viruses as vectors
Difficulties…
• many treatments necessary to have
sustained effect
• can’t control placement of inserted gene
• immune system may attack cells
• virus may cause disease
• many diseases are caused by more
than one gene
etc…
Setbacks…
• some patients have died during trials
• some patients developed leukemia
Successes…
• successful gene therapy in dogs for
blindness, in mice for Duchenne
muscular dystrophy, and in guinea pigs
for hearing loss
• some patients with congenital blindness
have had their vision almost completely
restored