Transcript Power Point Presentation

The Human Genome Project
Did You Know???
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Each cell holds six feet of DNA, if uncoiled and
knit together, all the DNA in your body would
stretch from earth to planet Pluto.
All the humans that ever lived represent less than
1% of the potential nucleotide arrangements.
The information in the nucleotide sequence is so
long (3 billion base pairs), that if the information
were written in sequence in linear form, it would
fill thousands of books the size of the Manhattan
telephone directory.
The Low Down on the HGP
It’s BIG: 15 years and its world wide.
Countries like Germany, Japan and France
are also very much involved.
 Its challenging and complex: 3 billion base
pairs to sequence.
 It’s expensive: $15 billion
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A little History…
In 1986 the Department of Energy was the
first federal agency to fund an initiative to
pursue a detailed understanding of the
human genome.
 In 1988, the National Institute of Health
joined the race.
 In 1990-91, the HGP really took off with
James Watson as the Director.
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What's a genome? And why is it
important?
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A genome is all the DNA in an organism,
including its genes. Genes carry information
for making all the proteins required by all
organisms. These proteins determine,
among other things, how the organism
looks, how well its body metabolizes food
or fights infection, and sometimes even how
it behaves.
What is the HGP???
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The Human Genome Project is an international
coordinated 15 year effort to characterize all the
human genetic material, the genome, by:
improving existing human genetic maps,
constructing physical maps of the entire
chromosomes and ultimately determining the
complete sequence of the DNA subunits in the
human genome.
 (They finished the working copy in July of
2000 and it should be finished completely by
the end of 2002)
Cont. of what is the HGP
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The ultimate goal of the HGP is to discover all of
the more than 50,000 human genes and make them
accessible for further biological study.
They want to focus on and ultimately understand
the most important human genes- the ones
responsible for serious diseases and those crucial
for healthy development and normal functions.
How Much Has Been
Sequenced???
As of July of 2000, roughly 90% of the
genome has been sequenced.
 The term “sequenced” means: completed,
edited, annotated, and submitted to the
GenBank.
 The rate of sequencing is increasing- it
roughly doubled last year and the year
before that.
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How is DNA sequencing done?
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Chromosomes, which range in size from 50
million to 250 million bases, must first be broken
into much shorter pieces
Each short piece is used as a template to generate
a set of fragments that differ in length from each
other by a single base that will be identified in a
later step
The fragments in a set are separated by gel
electrophoresis (separation step). New fluorescent
dyes allow separation of all four fragments in a
single lane on the gel.
Cont…
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The final base at the end of each fragment is
identified (base-calling step). This process
recreates the original sequence of As, Ts, Cs, and
Gs for each short piece generated in the first step.
After the bases are "read," computers are used to
assemble the short sequences into long continuous
stretches that are analyzed for errors, gene-coding
regions, and other characteristics.
Finished sequence is submitted to major public
sequence databases, such as GenBank
How???
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Constructing Maps
Genetic Linkage Map
Shows relative locations of specific DNA markers
along the chromosome.
Any inherited difference among individuals is
easily detectable in the lab and is a potential
genetic marker.
The human genetic linkage map is constructed by
observing how frequently two markers are
inherited together.
Cont…
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Value: inherited diseases can be located on a map
by following the inheritance of a DNA marker
present in affected individuals or absent in
unaffected individuals.
Genetic maps have been used to find the exact
chromosomal location of several important disease
genes such as, cystic fibrosis, sickle cell disease
and Tay-Sachs disease.
Applications!!!
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Knowledge about the effects of DNA variations
among individuals can lead to revolutionary new
ways to diagnose, treat, and someday prevent the
thousands of disorders that affect us.
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Some current and potential applications of genome
research include:
molecular medicine
microbial genomics
risk assessment
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Molecular Medicine
improved diagnosis of disease
 earlier detection of genetic predispositions
to disease
 rational drug design
 gene therapy and control systems for drugs
 pharmacogenomics "custom drugs"
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Microbial Genomics
new energy sources (biofuels)
 environmental monitoring to detect
pollutants
 protection from biological and chemical
warfare
 safe, efficient toxic waste cleanup
 understanding disease vulnerabilities and
revealing drug targets
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Risk Assessment
assess health damage and risks caused by
radiation exposure, including low-dose
exposures
 assess health damage and risks caused by
exposure to mutagenic chemicals and
cancer-causing toxins
 reduce the likelihood of heritable mutations
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ETHICAL AND PRIVACY
ISSSUES!!!