NLM and NCHGR are both components of the National Institutes of Health,
the Federal government's primary biomedical research facility, located in
"This map of human DNA, the literal thread of life, applauds the
richness of the human race in several ways," said Vice President Al Gore.
"First, it is an accomplishment attributable to the generosity and
cooperation of dedicated researchers around the globe. Second, it will
advance our understanding of the genetic basis of baffling diseases that
today cause suffering and reduce the quality of life of our family
members and fellow citizens. And very importantly, it puts students on
the cutting edge of science by providing them with an instantaneous
on-line educational tool containing the latest research information about
genes and their function in both health and disease," the Vice President
"By combining computer technology with biomedical research tools, this
map proves the power of a new multi-disciplinary approach to biological
science," said NIH director Harold Varmus, M.D. And it will make a
significant contribution to raising the level of scientific literacy
According to NLM director Donald A. B. Lindberg, M.D., "We are proud of
this remarkable voluntary collaboration among several of the world s
leading research scientists in molecular biology. The fact that these
data are to accessible over the World Wide Web, that is, accessible to
millions, means that for the first time, a high school biology student
and a university scientist can retrieve data on an equal footing,"
Taking full advantage of cutting-edge information technology, an
electronic version of the map organizes the details into a readily
accessible Internet site with extensive links to supporting data about
the DNA structure of the genes and the proteins they encode. In
addition, the electronic map is a mouse click away from on-line
references in the medical and research literature, which will aid
scientists in linking information about a likely disease gene to its role
in cell function.
The Internet site (http://www.ncbi.nlm.nih.gov/SCIENCE96/) will officially be on line at 4:00 PM Eastern Time, Thursday, October 24.
According to NCHGR director Francis S. Collins, M.D., Ph.D., "A map of
this detail gives disease-gene hunters who have narrowed their search to
a specific region on a chromosome about a 1 in 5 chance the gene they are
looking for has already been characterized by this effort. And thus, it
gives researchers a ready list of genes possibly involved in human
In addition to its value as a research tool, the electronic gene map
contains easily understood information useful to American students, who,
by using computers at home or in the classroom, can have instant access
to the most current information about our genetic constitution.
The goals of the Human Genome Project include building various sorts of
maps that represent different aspects of the 3 billion subunits, or
bases, of human DNA. The two major maps -- called genetic maps and
physical maps -- contain molecular markers scattered throughout the human
genome that help researchers locate the position of a gene. In most
cases, genetic and physical maps -- used in a technique called positional
cloning -- can tell a scientist the gene he or she is looking for is within
a few million DNA bases of a marker on a specific chromosome. The
slowest part of a gene hunt nowadays is finding and sorting through all
the genes in the target region and determining exactly which one is
responsible for the disease. Residing within those millions of bases may
be hundreds of genes and much more DNA, irreverently termed "junk DNA,"
because scientists don't yet know what it does.
Placing the 16,334 "genes" on the new map promises to change all that.
It is the first step in the Human Genome Project's effort to locate and
identify all 80,000-100,000 genes packaged along a human cell's 23 pairs
of chromosomes. From the gene map, scientists will have immediate
on-line access to information about which genes lie in the target region.
The sequence of those genes may well suggest which ones go to the top of
the list for further study.
This gene-hunting strategy, known as positional candidate cloning, has
already been used successfully to locate and isolate genes responsible
for Alzheimer's disease, inherited colon cancer, and other serious
About 10 percent of the 16,334 points on the map represent fully
characterized genes. The rest are distinct snippets of active genes,
small stretches of DNA that fall somewhere within a gene to let
researchers know it's there, but that still need more complete
characterization to learn what the entire gene looks like and what it
does. (Not all genes in the human genome are active all the time. Some
carry out functions only during fetal development and then turn off
completely. Others are active only in certain tissues. Some diseases
and birth defects are caused by genes that turn on or off in the wrong
place or at the wrong time.)
Efforts have been underway for the past few years in both publicly
funded and commercial laboratories to identify spots throughout the human
genome that contain active genes. Scientists developed a way to mark
those spots by identifying short, unique segments of the genes, called
expressed sequence tags, or ESTs. In just the past two years, the number
of ESTs corresponding to genes in the human genome and stored in public
databases has grown to nearly 500,000.
"Although everyone recognized the value of mapping ESTs, there was so
much redundancy in the databases, it just wasn't efficient or
cost-effective to map them all," said NLM's Mark Boguski, M.D., Ph.D.,
who along with Greg Schuler, Ph.D., examined the DNA sequences of over
123,000 ESTs, and boiled them down to a unique set of gene identifiers.
Meanwhile, scientists from around the world, including Tom Hudson,
Ph.D., at the NCHGR-supported genome center at the Whitehead Institute in
Cambridge, Massachusetts, used various techniques to map the location of
the ESTs throughout the human genome. Whitehead scientists, as well as
those at Stanford University in Palo Alto, California, were among the
largest contributors of points to the gene map.
Scientists from France, England, Canada, and Japan also helped to map
the ESTs, which resulted in the gene map tying together information from
the genetic and physical maps of the human genome.
"One of the remarkable aspects of this project was that everyone came
together to pool resources and build something bigger and more useful
than any one group could have done individually," Boguski said.