The Human Genome Project

Paula Erdmann

Copyright 1999

Almost every aspect that makes a person unique is due to genetic factors, from the color of an individual's eyes to the functions of white blood cells. The one thing that makes an individual's unique characteristics the hardest to understand is the fact that it is all composed of four bases in different patterns. These patterns of adenine, thiamine, guanine and cytosine are the only things that differ one human from the next. This genetic code is contained in every cell that is found in the human body. Gregor Mendel first discovered the foundations of inheritance in the nineteenth century. His discovery was the basis that has now made it possible for humans to learn more about the genetic code. Mendel's discovery has now turned in to a multi-billion dollar project. This project is known as the Human Genome Project (HGP).

Brief History

The HGP began as a joint effort between the Department of Energy (DOE) and the United States National Institutes of Health (NIH). The Department of Energy's initial reason for entering the project was to was to gain a better understanding of the potential health risks that were involved in energy use and the production of energy, especially the risks involved with radiation. Two years after the DOE proposed the idea of sequencing the entire human genome the NIH joined in the effort. The foundations of the project were laid and two years later, in 1990, the project was begun. The project was originally laid out to be a fifteen-year program that would have a budget estimated at three billion dollars (1).

The DOE and the NIH established five major goals for the HGP. The first goal is to identify all of the genes in human DNA. This goal is phenomenal when it is considered that there are an estimated 80,000- 100,000 genes present in the human genome. The second goal of the project is to obtain the sequences of three billion DNA base pairs that create the human DNA. The next two goals of the project are to store all of the data on databases and create tools to analyze this information. The final goal of the project is to tackle the ethical, legal and social issues that may arise during the time it takes to complete the project (2).

The completion time of the project has been accelerated due to new advances in technology. The new goals include having a working 90% draft sequence by the summer of 2000 and finishing the project by the year 2003. The finished project in 2003 would be a 100% high quality sequence of all of the base pair sequences of the human genome. The DOE and the NIH have also stated that one of the highest priorities of the HGP is to not only complete the project but to make all of the information available to the public (3). The early completion of the HGP does not come at a bargain price. The estimated budgets for 1999 alone are $89.8 million for the DOE and $225.7 million for the NIH, bringing the grand total to $315.5 million for one year (4).

The HGP is progressing faster than what was expected, but a race to be the first to complete the human genetic sequence has emerged and become very aggressive. For example, in 1998, the Perkin-Elmer Corporation and Dr. J. Craig Venter, head of the Institute for Genomic Research, announced that they intended to start a new genomics company. The companies' intent was to complete the sequencing of the genome within three years (2001) making their completion date the earliest yet to be announced. They believe that their new company will be able to provide this information faster and more accurately than the current possible methods (5).

Technical Aspects

The HGP is not using any one person's genetic sequence for this project. Samples from many people are being incorporated into a genomic library. The samples are taken from the sperm of males and the blood of females. Sperm is being taken from males because it contains the Y chromosome that female cells lack. The donations of sperm and blood are strictly anonymous. The person donating their blood or sperm will never know that it was used in the HGP. The scientist working to sequence the genome also has no knowledge of the identity of the person (6). In addition to sequencing the human genome, scientists have also been working on sequencing other species' genomes to aid in the process if the HGP. The genomes of Escherichia coli and Saccharomyces cerevisiae (Baker's yeast) have recently been completed. Researchers are also studying the genomes of Drosophila and laboratory mice to aid in the project.

Determining the three billion bases and approximately 100,000 genes of the human genome is being accomplished by sequencing. Scientists begin sequencing by cutting DNA with restriction enzymes. These enzymes cut the DNA at specific sites on the strand. The next step is to use gel electrophoresis to separate different sized fragments that may have been produced by different individuals when treated with the restriction enzyme. The gel allows different sized particles to move at different rates when an electric field is produced. The smaller fragments move more quickly down the gel than the larger particles. To create a clonal library, the DNA can be amplified by either using a cloning vector, such as a yeast artificial chromosome or a bacterial artificial chromosome, or by polymerase chain reaction (PCR) (7).

After a clone library is achieved, sequencing can begin. One of the most popular methods being used to sequence the human genome is the Sanger method. The first step of this method is to produce fragments that each end in a different base. These fragments are then combined with replication reagents. These fragments are then replicated, one batch of fragments producing only fragments that end with adenine, one batch only ending in guanine one in cytosine and one in thiamine. The fragments are then sorted by gel electrophoresis to allow determination of the sequence of DNA (7).

New developments in technology are constantly being funded to make the overall completion of the project not only faster, but also cheaper. The current price of sequencing a single base pair is between $2 and $10 using the Sanger method. The hope was to develop a technology that could lower that price to under a dollar per base pair. Systems have now been developed that contain greater numbers of lanes, and lower run times. A new machine can now read up to 75,000 bases per day (8). One of these systems is called Capillary Array Electrophoresis (CAE). This system involves the use of a laser to read ninety-six capillaries at one time. The time is measured that it takes for each one of the fragments to reach the laser-detector region (9). Other new technologies have also been developed, such as shotgun sequencing, directed approach sequencing and sample sequencing.

Concerns of the Human Genome Project

There are a variety of social legal and ethical concerns surrounding the completion of the HGP. These concerns vary in subject from clinical applications to commercialization to privacy. The DOE and the NIH estimated that these concerns would play a big role in the HGP. They developed a committee to deal with these issues. This group considers access to genetic tests, fairness of use of information in employment and insurance situations, confidentiality and storage of information and public education it's major priorities to be taken into concern for this project.

One of the most controversial topics surrounding the HGP is the issue of commercialization of the products resulting from the completion of the project. Most are concerned with who will win the "race" to complete the project and whether of not they will charge insane amounts for the public to obtain and use this information. For example, if a company such as the Perkin-Elmer Corporation succeeds in completing and patenting the HGP first will they commercialize the information or will they follow the goals et by the DOE and the NIH and offer the information publicly? There is no way of knowing what exactly will occur after the project is finished. The Perkin-Elmer Corporation has already contradicted themselves in dealing with this issue. The company has been said to believe that the HGP information has great commercial value but then they have turned around and also said that they plan to make the data publicly available (5).

Clinical applications of the project are also another major concern of the public. These applications may be able to aid the human population greatly in terms of healthcare. After a mutation has been identified, doctors can then begin to work on genetic screening processes. This will allow them to predict the possible onset of a genetic disease later in life. However, the main goal of clinical applications is gene therapy. Gene therapy would provide a treatment to those who are suffering from a disease. Eventually, gene therapy may even help doctors find a cure for many genetic diseases. Gene therapy is already being tested for genes that have been identified. Therapies are already being tested for diseases such as cystic fibrosis and Duchane's muscular dystrophy. One of the down sides to these clinical applications is the impact this information may have on human lives. Questions have also arisen about the adequacy of doctors. Some feel that doctors may not be educated about genetic technologies or the implications that these tests may have on their patients' lives.

Another ethical and social concern of the HGP is the issue that deals with fairness and confidentiality. When the sequencing of the human genome is completed clinical applications are going to increase. This means that genetic screening may become a lot more common than previously. A majority of the public is concerned with the impact these tests could have on their employment opportunities and insurance premiums. In a survey, conducted by the DOE/NIH Working Group on Ethical, Legal and Social Implications of HGP, "nearly seven out of ten Americans are concerned that genetic information may be used against them" (10). In 1995, a set of guidelines was written to advise lawmakers to try and prevent insurance companies from raising rates or deciding eligibility based on genetic information. These, unfortunately, were merely guidelines and not a law. Luckily, in 1996, and act was passed to prevent the increase of rates for group healthcare because of genetic status. This act does not ensure privacy, however. Many other acts have been proposed to congress but are still pending (10).

My Opinion on the Human Genome Project

I believe that the HGP will provide the world with a wealth of information. This information has to be used with great caution in order to prevent exploitation and misuse. If handled with care, the HGP will be the one of the greatest accomplishments in the next century. The clinical application possibilities are endless. Gene therapy can improve the quality of living of many individuals who are suffering from genetic diseases currently. This will improve their quality of living and ensure better lives without a lot of the pain and suffering. Hopefully, the next discoveries will be the cures to these diseases that plague so many individuals in the world today. The only reason that any of this would be possible would be do to the completion and public knowledge of the human genome.

References

1) Website #1: The Genome Project- Why the DOE? Obtained from the WWW: http://www.ornl.gov/hgmis/publicat/tko/02_why.html
2) Website #2: Human Genome Project Information. "About the Human Genome Project." Obtained from the WWW: http://www.ornl.gov/hgmis/about.html
3) Website #3: Human Genome Project Information. "Human Genome Project Progress." Obtained from the WWW: http://www.ornl.gov/hgmis/project/progress.html
4) Website #4: Human Genome News. "HGP Leaders Confirm Accelerated Timetable for Draft Sequence." Obtained from the WWW: http://www.ornl.gov/hgmis/publicat/hgn/v10n3/01hgpdraft.html
5) Website #5: "Perkin-Elmer, Dr. J. Craig Venter, and TIGR Announce Formation of New Genomics Company." Obtained from the WWW: http://www.tigr.org/new/press_release_may98.html
6) Website #6: Human Genome Project Information. "Facts About Genome Sequencing." Obtained from the WWW: http://www.ornl.gov/hgmis/faq/seqfacts.html
7) Website #7: "Tools of the Trade." Obtained from the WWW: http://www.ornl.gov/hgmis/publicat/tko/05_tools.html
8) Website #8: "Exploring the Genomic Landscape." Obtained from the WWW: http://www.ornl.gov/hgmis/publicat/tko/04_exploring.html
9) Website #9: DOE Human Genome Program Report. "Capillary Array Electrophoresis." Obtained from the WWW: http://www.ornl.gov/TechResources/Human_Genome/publicat/97pr/04g_sequ.html
10) Karanjawala, Zarir E. "Genetics in the Context of Medical Practice." The Journal of the American Medical Association. Nov. 4 1998, v280n17, p1533.

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