Class Notes
Human Genome Project,
Gene Therapy, & Cloning
Questions/Main Idea:
How much DNA is in one
cell?
What is the Human
Genome Project?
What were the goals of
the human genome
project?
How did they do it?
Name: _______________________________________
Period:_______________________________________
Date: _______________________________________
Notes:
 Human genome = 46 chromosomes
 about 3 billion base pairs
 one base pair is 0.00000000034 meters
 DNA sequence in any two people is 99.9% identical – only 0.1% is
unique!

An international effort to decipher the DNA blueprint of a human
being

To sequence and determine the exact order of nucleotides (A,T,C,G)
for all of the DNA in a human cell
 To determine which sections of DNA represent the individual genes
 To store this information in databases for analysis
1. DNA was collected from 1000s of volunteers
2. Samples were sent to Human Genome Project centers around the world
3. Scientists at centers perform DNA sequencing and analysis
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Compare the genome of humans with other organisms
Discover DNA and its functions
Investigate the interactions between DNA sequences, gene products,
and environmental factors
Analyze genetic variation between individuals and populations
How can we use the
information?
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Better understanding of human disease
Personalized medicine
Greater insight into the brain
Insight into human origins
Identify genetic susceptibility to disease
What is Gene Therapy?
Replacement of an abnormal protein with a normal one
How does Gene Therapy
Work?
1. Isolate the normal sequence for the protein and package it into a virus
(vector)
2. Infect a target cell, usually the one with the illness, such as a liver or
lung
3. The virus uses the normal sequence to produce the missing protein and
the cells return to normal
4. Lasts the life of the cell then patient must be retreated.
What are the problems
with Gene Therapy?
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What is there left to do?
Short lived, so patients have to go through multiple rounds
Immune response to foreign invaders
Problems with the viruses
Very expensive
Multigene disorders

What is cloning?

Cloning is the creation of an organism that is the EXACT genetic copy
of the mother
Identical twins are natural clones, they share 100% of their DNA
1. Remove the nucleus from an egg cell and a regular cell from a donor.
2. Fuse the enucleated cell with a regular cell by electric shock
3. The new fused cell begins dividing, just as a fertilized egg would
4. The embryo is placed in the uterus of a foster mother and allowed to
develop normally
5. The foster mother gives birth to a genetic clone of the original donor!
How do you clone an
organism?
Why might we want to
clone?
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For medical purposes
Revive endangered species or extinct species
Reproduce deceased pets
Any reason to clone a human?
What are the risks of
cloning?
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High failure rate
Problems later in development
Premature aging
Abnormal gene expression
Summary: