The Human Genome Project

Rian Lee

Copyright 1999

The Human Genome Project (HGP) is a project coordinated by the U.S. Department of Energy (DOE) and the National Institute of Health (NIH). The HGP began in 1990 and was scheduled to be completed in 2005. The goals of the project are to identify all the genes in the human genome (estimated to be 80,000 - 100,000 total) and develop the complete human DNA sequence. After the sequencing is done, a database with all the sequence information can be made and data analysis tools can be developed to use the information. The HGP will then have to consider ethical, legal, and social issues.

A new 5-year goal was approved in 1998 in which the HGP could be finished two years earlier than first planned in 1990. The new goal would provide a working draft of the human genome by 2001 and the complete human sequence by the year 2003. NIH and DOE are expecting to sequence 60-70% of the human genome. The other 30-40% will be sequenced by the Sanger Center, a project funded by the Wellcome Trust, and other international partners' (1).

The task of sequencing the human genome is time consuming and very tedious. Since the start of the HGP, there has been a very large emphasis on developing new technology to speed progress and cut costs. The DOE has played a large part in the advancement of this new technology. Much of the community at first was curious as to why the DOE would be involved in such a project as the HGP. The DOE is interested in a better understanding how energy and energy-production technologies affect the health risk of people, with the most interest in the effects of radiation (2). The DOE and other private sectors have helped in the advancement of technology very rapidly; the result is lower cost and faster sequencing of the human genome.

The HGP is making all of the human sequences developed thus far available to the public in hopes that the public can benefit from the project. The private sector is also contributing to the human sequencing project. One such company is Celera Genomics. The President of Celera Genomics, J. Craig Venter, is promising to give away the human genome sequence once the company has completed the sequence. Although he is just beginning to set up a high throughput lab, he believes he can generate the human genome sequence in 18 months. Many people are skeptical about how he can develop the human genome and provide it to the public without any costly strings attached. Celera plans to patent many human genes and a large set of single nucleotide polymorphism's (3). If Celera Genomics is the first to sequence the human genome, there may be a price to pay for the sequences that revolutionize the biological community.

Another task of the HGP is to determine variations in the human genome. One approach is to map single nucleotide polymorphism's (SNPs). By mapping the SNPs, scientists can gain a better understanding of the variations and the functional aspects of these variations. "A map of 100,000 SNPs (one SNP per 30,000 nucleotides) is likely to be sufficient for studies in some relatively homogenous populations, while denser maps may be required for studies in large, heterogeneous populations" (2). These maps could provide markers that identify disease genes in humans.

Once the mapping and the complete human sequence are developed, the researchers have to determine the function of the genes. The genes function is the critical data that needs to be determined. Researchers need to determine how the genes are arranged within the chromosomes, how they function with respect to environmental factors, and how variation within genes from one person to the other will affect or not affect that person. Another aspect is comparative genetics that studies the similarities and differences between closely related species. The HGP is currently developing genome sequences of other species to compare to the human genome. The other genomes already sequenced are E. coli, S. cerevisiae and C. elegans. D. melanogaster and mouse are also being sequenced. For comparative genetic studies, other organisms will also have to be sequenced to compare genes of similar species. With all the sequencing information being developed, a database will have to be made to store all this information.

Bioinformatics is necessary to develop a database that can hold the never-ending information coming from the research of the HGP. "Databases are the ultimate repository of the HGP data. As new kinds of data are generated and new biological relationships discovered, databases must provide for continuous and rapid expansion and adaptation to the evolving needs of the scientific community" (2). These databases will need to be user-friendly to other scientists utilizing the data, in such areas as functional genomics and comparing sequences (similarities and variances). Software will also need to be available for the scientists to access the database and have the ability to do computational biology.

The next subject that needs consideration is the benefits of the human genome project. When the sequence of the human genome is completed, scientists will be able to detect the variability within the human genome and detect genes involved with a disease. Multiple genes are often involved with a single disease. A disease with multiple genes will be more difficult to analyze. Therefore, a cure or prevention of the disease will take longer.

The completion of the human genome sequence is the first step in a long process to discover all the variations in the genes and identify which genes cause certain diseases. With the advancement in technology, it will be easier to understand the variability within genes in the human population than initially sequencing the human genome.

Possible applications with genome research are molecular medicine, microbial genomics, risk assessment, bioarchaeology, anthropology, evolution and human migration, DNA forensics, agriculture, livestock breeding, and bioprocessing (4). Molecular medicine will open the door for more rapid and specific diagnostic tests with the use of gene therapy. These tests are involved with the genes and how augmenting or replacing the defective genes can be corrected by gene therapy.

The DOE, which had an interest in microbial genomics, initiated the microbial genome project (MGP). The knowledge acquired from the MGP will provide information leading to beneficial uses of bacteria. Some of these benefits include energy production, detection of environmental pollutants, reducing toxic waste, and industrial processing. Risk management will be used to determine the risks associated with exposure to radiation, mutagenic chemicals, and carcinogens that could lead to heritable mutations. A better understanding of the human genome and comparisons to other species may help in understanding evolution and the similarities and differences between species. DNA forensics can benefit from better markers to allow for very accurate identification.

Agriculture and livestock breeding will also benefit from the HGP. The plant and livestock industries will be able to develop superior lines that are stronger and have increased disease resistance. This may reduce costs and provide a better quality of food. The benefits of the HGP will be substantial. An important question is what ethical, legal, and social boundaries will be set for the use of this information.

The HGP established a committee to deal with ethical, legal, and social implications. This committee, known as The Ethical, Legal, and Social Implications Program (ELSI), will have a huge undertaking in defining these boundaries. Many issues will need consideration by ELSI relating to the HGP. Some of these issues relate to discrimination, privacy, testing, screening, counseling and gene therapy.

Genetic discrimination occurs when people are unfairly treated because they carry a disease gene even when no symptoms of the disease are apparent (5). Discrimination may also be seen in non-symptomatic gene carriers whose children could develop a genetic disorder. One of the possible outcomes of such discrimination may involve health insurance companies. Insurance companies may drop coverage for an individual who carries a gene that could lead to a disease. Insurance companies may also drop coverage for an entire family because a genetic disorder was discovered in one individual of the family. Another possibility involving insurance companies is the concern that pregnant women may have their fetus test positive for a genetic disorder. If parents had a fetus test positive for a genetic disorder, the insurance company may refuse future coverage during and after the pregnancy. Thus, allowing them to avoid the medical expenses related to the genetic disorder. "Health insurance based on a person's genes is one of the most common forms of discrimination" (5).

Other forms of genetic discrimination involve the workplace, school, and the adoption of a child. In the workplace, a person could be fired due to genetic disorders that would lead to increased costs incurred by the employer. Children could become outcasts in a school for having the possibility of developing a genetic disease. People could also be discriminated against while attempting to adopt a child. If the parents have the potential of developing a genetic disease or disorder, they may not be able to adopt a child just because they carry the potential disease gene. Genetic discrimination will become a very important topic as the HGP progresses.

Privacy is another issue that needs to be addressed by ELSI. Privacy is defined as "the limited access to a person, the right to be let alone, and the right to keep certain information from disclosure to other individuals" (6). Privacy is related to genetic discrimination in some aspects such as insurance and employment. Privacy is also a consideration involving other non-medical issues that involve genetic information such as criminal law, personal-injury litigation, forensics, and domestic relations. Unproven theories of genetic predisposition to violent behavior are currently being attempted in criminal cases. Accident victims may be required to undergo genetic testing to determine their life expectancy. This information would place a monetary value of their life expectancy before the accident.

Genetic information may be abused by non-medical institutions that gain access through medical records and use it to define a person based on their genetics and any genetic disorders the person may have. Genetic information is different from other medical records for many reasons. "It reveals parentage, reproductive options, and future health risks; it goes to the essence of who and what an individual is; and it's regarded as unique by individuals and third parties, who often overuse it" (6). Privacy will become very important when genetic testing is done on an individual when others want access to that information.

Genetic testing, screening, and counseling are other areas that require discussion. As new genes are identified by the HGP, new tests will be developed to determine whether an individual will be at a higher risk for a certain genetic condition. These tests will be able to inform people of possible genetic disorders that may develop into a disease or the potential of passing the disease gene onto their offspring. Genetic testing is valuable and allows people to know if they are carriers of certain genes. This will permit them to make decisions based on genetic knowledge. The knowledge obtained from genetic counseling could help the person avoid harmful environmental elements. Avoidance of environmental elements known to be associated with diseases would benefit the health of an individual, prolonging their life. Genetic counseling could also reduce the risk of passing the disease genes to offspring.

There are also negative aspects. A person's medical record may show genetic disorders that could lead to discrimination and the loss of privacy. Children testing positive for a disorder may not be allowed to live a life without restrictions placed upon their activities. Genetic testing and counseling can be very beneficial in some aspects, but testing children and other individuals with unknown cures may cause them to face discrimination, loss of privacy, and may subject them to a life full of restrictions.

Gene therapy is an issue that will become very important with the progress of the HGP. Gene therapy is a treatment by which normal genes are introduced into an individual's cells to modify or correct the function of the gene. There are two types of gene therapy. One is the treatment of somatic cells, which includes all the cells of the body except the sperm and egg cells. "If gene therapy does become practicable, the biggest impact would be on the treatment of diseases where the normal gene needs to be introduced into only one organ" (7). This form of gene therapy is a variation of somatic cell gene therapy.

The other type of gene therapy is the replacement of germline cells that affect the genetic heritage of offspring. The ultimate outcome of the replacement of an individual's gene through gene therapy would also affect their children. "Germline therapy would change the genetic pool of the entire human species, and future generations would have to live with that change" (7). Gene therapy can be very beneficial to individuals with diseases that cause themselves harm. One such disease is Lesch-Nyhan disease. Individuals with Lesch-Nyhan disease develop an involuntary self-injurious behavior. Gene therapy for diseases like this would benefit these individuals. Other individuals look at their disease differently. Some individuals that develop physical disabilities from a disease suggest that developing a cure may demean them and their individuality that arose from the disability (5). Diseases such as this may not be given the same public understanding for gene therapy as the more deleterious disorders.

The Human Genome Project can provide a vast amount of information about humans and the genes involved in diseases. I am in favor of the HGP and the information that can be attained from it. As the HGP discovers new genes and identifies these genes as being beneficial or detrimental to humans, a new wave of medical technology will develop. Genetic screening can be beneficial to individuals at risk by determining if a person is carrying a disease gene and the information on how to possibly prevent the gene from expressing itself as a disease. Individuals could benefit from the knowledge of changing their lifestyle or exposure to environmental elements and thus prevent a gene from causing a disease. Ultimately, gene therapy is very important because of its ability to change the genetic makeup of the individual and eliminate the disease gene.

Sequencing other organisms will also provide very important information. The comparisons of other organism sequences will provide information that will be valuable. With the understanding of genes of one species, knowledge about related genes in another species will become easier to interpret. The MGP will supply information about bacteria and the beneficial uses for the environment.

Caution must be used with the new information available from the HGP. ELSI has been formed to provide guidelines by which the HGP information will be used. These guidelines will have to be detailed to avoid ambiguity and regulated to avoid unethical use of the information. The intellectual perspectives stemming from the research of the HGP will become very interesting in the field of life sciences. The potential of increasing our quality of life may reflect the importance the HGP will have on our society.

References

1. Collins, Francis S. et al. New Goals for the US Human Genome Project: 1998-2003. Science 282, 682-689 (1998).

2. The Genome Project-Why the DOE?, http://www.ornl.gov/hgmis/publicat/tko/02_why.html, accessed 10/07/99.

3. Marshall, E. A High-Stakes Gamble on Genome Sequencing. Science 284, 1906-1909 (1999).

4. Potential Benefits of Human Genome Project Research, http://www.ornl.gov/hgmis/project/benefits.html , accessed 10/07/99.

5. Davis, S. The Human Genome Project: Examining The Arc's Concerns Regarding the Project's Ethical, Legal, and Social Implications, http://www.ornl.gov/hgmis/resource/arc.html, accessed 10/13/99.

6. Rothstein, M. A. Human Genome news "Protecting Genetic Privacy: Why It Is So Hard To Do", http://www.ornl.gov/hgmis/publicat/hgn/v10n1/14roth.html, accessed 10/07/99.

7. Gene Therapy - An Overview, http://www.accessexcellence.org/AB/BA/Gene_Therapy_Overview.html, accessed 10/07/99.

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