The most precious piece of information imaginable — the human genome — was publicly released in formal data reports by two teams of researchers last Monday, just in time for the birthday of Charles Darwin, who jump-started our biological understanding of nature and evolution.
The achievement, however, is not so much the fuel for an intellectual revolution on par with Darwin’s discoveries, but rather it represents “a remarkable technological achievement analogous to putting the first man on the moon,” according to Prof. Charles Aquadro, molecular biology and genetics.
“It changes the way we can do science. Now we can look at a whole host of genes in humans and better understand the complexity of many groups of organisms,” said Aquadro, who works on related research.
The present sequencing of the human genome is only the beginning, however, and the deeper meaning of the scientific milestone must be gleaned with time, stressed Craig T. Basson, assistant professor of medicine and director of the Molecular Cardiology Laboratory at the Joan and Sanford I. Weill ’55 Medical College.
In two separate articles published in Science and Nature magazines, the rival groups — Celera Genomics, a private corporation, and the International Human Genome Sequencing Consortium, a group of publicly funded academic centers — admitted that the genome analysis is intended to be a preliminary draft that will provide direction for future study.
The teams jointly announced last June that each had independently assembled the human genome, but it has taken until now to analyze and publish their findings — DNA blueprints that look remarkably similar despite the different decoding methods.
Physically, the human genome is miniscule in size but vast in its informational content. If printed in standard type, it would cover over 120,000 pages of this newspaper.
After mapping out the principal features of the genome’s complex architecture, the teams have come up with sequences that are recognizable in places but riddled with gaps throughout. They found few functioning genes, a lot of junk and fragments left behind by bacteria.
Both research groups stressed their surprise at discovering that the genome contains only a third as many genes as has long been thought.
In contrast to the 100,000 gene estimation published in most textbooks, the analysis has suggested that humans have a mere 30,000 genes — less than twice the number of genes found in a roundworm and only 17,000 more than are found in fruit flies.
Confronted with this seeming paradox between human complexity and the small number of genes detected, scientists have been pressed to offer an explanation.
“I don’t think there is a paradox,” said Basson, who cautioned against trying to classify a mysterious genome with many unfamiliar and disparaging elements.
“We run into problems when we try to apply rules to interpret a database using only genes that we know. If you think outside the box, it’s possible we’re missing a whole lot of genes,” Basson said.
He added that proteins and the environment may be more important than we thought in promoting diversity.
Even if these discrepancies are reconcileable, the effect on human pride is another matter.
“Homo sapiens, as a species, needs to get over its superiority complex. It should be enough to be one among the multitude of fascinating organisms,” said Greta Hume grad, explaining how people may have trouble admitting that, up close, we humans do not look all that different from fruit flies.
“The early research that humans have a small number of genes does not denigrate from our nobility of a species so much as it connects us more with other species and stresses the interrelatedness of all living things,” said Father Michael Mahler, Catholic director and chaplain at Cornell.
“Any scientific advance is a potential blessing and a curse,” Mahler added.
The low number of genes can be seen as good for medicine because there are fewer genes to understand, according to Aquadro.
“By focusing on the differences between humans, we will have the opportunity to improve diagnoses and to understand why some drugs work for some people and fail to cure others,” Aquadro said.
Taryn Mattice, chaplain for Protestant Cooperative Ministry, characterized herself as both “optimistic” about the genome’s predicted ability to address disease and “cautious” about the concern that the public knowledge of the genome will raise many new ethical questions in terms of job discrimination and cloning humans.
“I am afraid that there’s an inclination to see the world and human life in mechanical ways. Humans seem to have the ability to use information in ways that are not kind,” Mattice said.
Admitting that she too worried about people’s reactions, Victoria Walker ’01 said, “It’s exciting but it’s also kind of scary that we know so much.”
Marsha Davis ’01, a pre-med biology major, thought that the positives outweighed the negatives as she spoke of the possibilities that the human genome sequencing has for enhancing her chosen field.
“As a future doctor, I can say it’s exciting … incredible … indescribable … a major, major accomplishment …. We should celebrate it more,” Davis said.
Biologists will likely be celebrating for a while, as they labor to decode the genome’s complex and mysterious message. At this point, the instruction manual for making a human organism stands as an enigma — posing almost more questions than it does answers.
“Sequencing the human genome is like discovering the Rosetta Stone. It is just the beginning,” said Hume, adding, “Now, the really hard and interesting work of interpreting and transcribing can continue more quickly.”
Archived article by Jennifer Roberts