Understanding Genes

Understanding Genes
The Human Genome Project is probably one of the greatest breakthroughs in human history. Read on to know more about it ...
The book of genetic instructions for the human body is complete to an accuracy of 99.99%. This is a scientific achievement once deemed impossible, but now considered the foundation for new era of medical advances, an international research team said. With the entire sequence in hand, and available to scientists worldwide, experts predict that it will lead to new drugs, better forecast of people's health, and new ways to treat and prevent many of the devastating human illnesses. A joint statement from the leaders of France, Britain, Germany, Japan and China, including US President George W. Bush, said "The genetic map provides us the fundamental platform for understanding ourselves from which revolutionary progress will be made in biomedical sciences and in the health and welfare of humankind."

The International Human Genome Sequencing Consortium, led in the United States by the National Human Genome Research Institute (NHGRI), and the Department of Energy (DOE), on April 14, 2003, announced, the successful completion of the project, more than two years ahead of schedule.

The international effort to sequence the 3 billion DNA letters in the human genome is considered by many to be one of the most ambitious scientific undertakings of all time, even compared to splitting of the atom, or landing on the moon." The Human Genome Project has been an amazing adventure into ourselves, to understand our own DNA instruction book, the shared inheritance of all human kind," said NHGRI Director Dr. Francis S. Collins, leader of the project since 1993. "All project goals have been completed successfully - well in advance of the original deadline and for a cost substantially less than the original estimates."

When the Human Genome Project was launched in 1990, many in the scientific community were deeply skeptical about whether the project's audacious goals could be achieved, particularly given its difficult timeline, and relatively tight spending levels. At the outset, the US congress was told the project would cost about $3 billion, and would be completed by the end of 2005. In actuality, the project was finished two and a half years ahead of schedule and at $2.7 billion, significantly under original spending projections.

"Never would have dreamed in 1953, that my scientific life would encompass the path from DNA's double helix to the 3 billion steps of the human genome. But when the opportunity arose to sequence the Human Genome, I knew it was something that could be done - and that must be done," said Nobel Laureate Sir James D. Watson, President of Cold Spring Harbor Laboratory in Cold Spring Harbor, N.Y. "The completion of Human Genome Project is a truly momentous occasion for every human being around the globe"

Besides delivering on the stated goals, the International network of researchers has produced an amazing array of advances that most scientists had not expected until much later. These "bonus" accomplishments include: an advanced draft of the mouse genome sequence published in December 2002; an initial draft of the rat genome sequence produced in November 2002; the identification of more than 3 million human genetic variations, called single nucleotide polymorphisms (SNPs); and the generation of full-length complimentary DNAs (cDNAs) for more than 70% of known human and mouse genes.

For scientists seeking to understand the role of genetics in human health and disease, the project's finished sequence represents a significant advance over "working draft" that was announced in June 2000. The working draft covered 90% of the gene-containing part of the sequence, 28% of which had reached finished form, and contained about 150,000 gaps. The finished version of the human genome now contains 99% of the gene-containing sequence with the missing parts essentially contained in less than 400 defined gaps.

These remaining gaps represent regions of DNA in the genome with usual structures that cannot be reliably sequenced with current technology. These regions however, appear to contain very few genes. Closing these gaps will require individual research projects, and new technologies rather than industrial-scale efforts of the Human Genome Project. The high-throughout sequencing of the human genome has thus reached its natural conclusion.

Biomedical researchers now have a tremendous foundation on which they can build the basis of science and medicine of the 21st century.