 When
Biology Makes History
By Katie Beaver '03
To understand Cathy Silver Key's role in the Human Genome Project, which
neared completion earlier this year with the announcement that scientists
had sequenced human DNA, she says to think of it as working in a library.
Key, an adjunct assistant professor of biology at Elon since 1999, worked
as a lab technician with the project in its planning stages after graduating
from the University of Missouri at St. Louis. She helped build part of the
human-yeast DNA library that was published this year. "This library
potentially contains all the information for human life," she says.
To envision how scientists sort out all the genes in a human cell, Key says
to think of a library full of books. "Just like each book contains
information, each piece of DNA or gene contains information for the cell,"
she says. "In a library, the books are sorted according to topic and
in alphabetical order. To map the human genome, scientists create a library
that contains DNA rather than books."
Some Key Terms
DNA: the basic chromosomal material that encodes genetic information.
The DNA is the language of the cell, consisting of a 4-letter alphabet.
Gene: the fundamental unit of heredity. Many genes code for
proteins that give each organism its characteristics, such as appearance
and behavior.
Genome: the complete set of DNA contained within a cell.
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Key and her colleagues placed samples of DNA into yeast organisms. These
yeast cells can carry the human DNA, storing it like volumes of books on
a library shelf. "In a library, you take books off the shelf to read.
In the yeast, you could find a piece of DNA and figure out what it's about,"
she says. Scientists then have to sort through the human "books" of information
and place them in the correct order, Key says. "We tried to see how
each piece fit into the rest of the DNA, like trying to put together a puzzle."
As the pieces slowly came together, scientists came closer to realizing
the goals of the Human Genome Project. "Most of all, the scientists
just wanted to know the sequence of human DNA," says Key. "Basically,
scientists have been working to create a map of all the genes that are found
in a human cell."
The project, coordinated by the U.S. Department of Energy and the National
Institutes of Health, reached its projected goal last summer under the leadership
of scientist Francis Collins and his worldwide team of researchers. The
announcement came years ahead of schedule (in part because a company named
Celera competed with the government-funded project and also published a
map of the human genome this year) and opened many doors to scientific and
medical discoveries. "These findings will be translated into something
that will be applied to help society," Key says.
Once all the genes have been mapped and scientists figure out what each
gene does, Key says that doctors could use the information to diagnose genetic
diseases and perhaps treat them more effectively by replacing the
damaged DNA causing the disease with undamaged DNA. Key says that some diagnostic
tests for disease genes are already available, and gene therapy (the process
of replacing a damaged gene with an undamaged gene) has been attempted.
"Of course, this raises all sorts of ethical questions at the same
time as it increases knowledge," she says. "Do we really want
to know everything that's wrong with us? Who should have access to the information?"
Despite these ethical issues, Key says the project will be beneficial to
the public. "It's good to understand what's causing the disease because
that way, we can work on potential cures. People want to save their relatives
and save themselves, and I know they think it's worth the expense."
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Key's Role in the Human Genome Project
Cathy Silver Key says she got involved in the Human Genome Project simply
because she was looking for a job after graduating from the University
of Missouri at St. Louis. She worked on the project from 1988-89 at the
Center for Genetics and Medicine at Washington University in St. Louis.
(She received her Ph.D. from UNC's Department of Microbiology and Immunology
in 1997.)
Key says it was exciting to participate in the historical process as a
lab technician with the Human Genome Project. "My job was to take
the human-yeast DNA that was in a test tube and build the library of yeast
cells that contain the hybrid DNA," she says.
"To do this, I would 'punch' holes into the yeast cells using a chemical
solution. Then the human-yeast DNA would be mixed into the tube with the
'holey' yeast cells. The hybrid DNA would then go into the cells,"
she explains. "In the yeast cells, the human-yeast DNA could be propagated
on little plates that contained nutrient agar (food for the yeasts). After
a time, I would 'crack' open the cells -- like cracking a book -- and
try to 'read' the DNA code that was inside."
 Key
says she was honored to work with researchers Maynard V. Olson, recipient
of the 1992 Genetics Society of America Medal and co-author of the Nature
article releasing the 2001 draft of the human genome, and David Schlessinger,
who was the first graduate student out of James Watson's laboratory. Watson
was the co-discoverer of the structure of DNA.
The experience was a rewarding one because of the project's place in history.
"I got the thrill of participating in a historical process,"
she says. "As I attended frequent lab meetings, I was privileged
to listen to scientists figure out how to put the massive jigsaw puzzle
that is the human genome together."
 Key
says that mapping the human genome is just one part of the puzzle, however.
"We broke the DNA code, but we still do not know all the secrets
that the genome holds. The Human Genome Project is a big step in the right
direction." She says that once scientists figure out what all the
genes do, the next step is to study the proteins made from the genes.
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