Biomedical Engineering Reference
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methods in molecular biology and computer programs are then used to de-
termine the relationship of these pieces to each other within the chromo-
somes of living cells. Then the large pieces are broken randomly into small,
overlapping fragments, the base sequence of each of these fragments is de-
termined, and a computer program reconstructs the sequence of bases that
comprised the original, naturally occurring genome.
The whole-genome shotgun method used by Celera skips the steps in-
volving the long pieces of DnA and simply blasts the whole genomic DnA
sample into tiny, randomly generated, overlapping fragments. These frag-
ments are then sequenced by an automated process and aligned into the en-
tire genome by computer programs.
The hierarchical method is slower, more expensive, and requires more
manual labor than the shotgun approach. The shotgun method lends itself
better to automated processing but is more prone to error due to the oc-
currence of short sequences of bases that are repeated many times at many
locations in the genome.
The Public Consortium and the Celera group both used DnA derived
from anonymous donors for their projects. The ihGsC used DnA from
eight males of unknown ethnicity for their starting material, with one do-
nor's DnA comprising 75 percent of the entire sample. Celera used DnA
from two males and three females (one African American, one Asian Chi-
nese, one hispanic mexican, and two Caucasians), with one donor's DnA
comprising 66 percent of the entire sample.
Competitors race toward the finish and then cooperate.
on June 26, 2000,
President Bill Clinton, Prime minister Tony Blair, francis Collins, and
J. Craig venter announced the completion of a rough draft for the sequence
of the 3.1 billion bases in the human genome. Their announcement was the
culmination of a fantastic story of international resolve and cooperation,
scientific competition, personal rivalry, and human pride.
During the first eight years of the project, the Public Consortium pro-
gressed methodically, steadily, and slowly toward the 2005 goal. its em-
phasis was on accuracy and openness. each day the consortium posted the
details of its progress on a public website.
meanwhile, venter and his group at Celera (latin for “quick”) Ge-
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