What if disease could be predicted before it happened? No, this is not a fictional health-care version of Minority Report, but a possible end science is quickly developing towards. What began as an inquiry into how diseases are passed on to offspring has been steadily progressing towards a disease-predicting mechanism that could drive the future of healthcare this century. Leroy Hood, president of the Institute for Systems Biology, describes this mechanism as one that incorporates the four elements of P4 medicine: predictive, preventive, personalized, and participatory. What this boils down to is the following scene: imagine going to the hospital not for treatments of diseases, but rather for personalized check-ups. Through these check-ups, physicians monitor changes in your body and ascribe medications to stop potential diseases from ever developing. People would never have diseases again … or so the thought goes.
At the core of this vision is specificity. According to Hood, many current medical treatments today act on a “trial and error” basis; they remedy an affected site but also cause unwanted effects on healthy, nearby sites as well. An example of this can be seen with cancer treatment. While chemotherapy kills cancerous cells, it also harms surrounding cells. Nowadays, diseases have split into multiple subtypes, with each subtype giving more information on the cause and nature of the disease (similar to how each animal phylum is divided into smaller classes). Breaking down diseases into smaller levels creates more effective and cost-efficient treatments, especially due to a decrease in side-effects. Yet, as Hood and other health care professionals believe, diseases will be subdivided into even smaller categories, possibly to the extent that a sublevel of a disease is specific and unique to the person affected by it.
Classifying diseases according to each person allows for highly specific treatments; however, arriving at such a deep understanding of each person’s body is difficult. What genes are present? What proteins come from those genes? How do those proteins interact with each other to make a body function? Scientists study several fields such as systems biology and proteomics (study of proteins) to explore these questions. Ideally, each person would have her entire set of genes (genome) sequenced and her body completely mapped out as a network of proteins interacting with each other. Mapping the body unveils the mystery, allowing every component of it to be integrated into a network. Using this network, health care professionals could see how a disease might spread through the body and develop treatments designed to specifically target the disease before the disease ever causes symptoms. To summarize: diseases would be stopped before they even began.
Some progress has already been made towards this ideal. A recent study in 2009 on prion infection traced its progression in mice. For 20 weeks, researchers studied the genes that contributed towards the disease and the proteins that were involved as well as other symptoms of prion disease. Using the data collected, they were able to map several networks that involved with prion disease, relying on the idea that disruptions in these networks contributed towards the disease. Scientists are currently using these methods to map the networks involved in the development of cancer; the results of this research could lead to a better understanding of how cancer starts and how to to prevent it.
Yet, even if it were possible to stop diseases such as cancer from developing, would society be willing to accept this vision? While this may seem an incredulous question, it is one that must be considered. Would individuals be willing to reveal their genetic makeup despite the possibility of discrimination? Can genetic information be used properly by the government? These and many other ethical questions have to be considered before society can approach this state.
A few of these issues surfaced in the 90s when the topic of “genome sequencing” became popular through the Human Genome Project. Genome sequencing involves mapping out all of an organism’s genes to see how those genes interact with each other and produce different phenotypes, or expressed characteristics, of a person. Since some of those characteristics could include susceptibilities to different diseases, genome sequencing could offer insight into how severely a disease could be expressed in a person and in his offspring. These insights raised a hairy issue: if insurance companies were to obtain a person’s genetic code, they might raise the cost of insurance if the person displayed a higher risk for a costly disease and decrease the price for others with a lower risk. Seeing the potential for discrimination, the government passed the Genetic Information Nondiscrimination Act (GINA) in 2008, which both made it illegal for employers and health insurance companies to discriminate based on a person’s genetic code, and prevented them from requiring employees and consumers to have their genomes sequenced.
When GINA was passed four years ago, the field of genome sequencing was not as developed as it is now. While the first whole genome sequencing project took thirteen years (1990-2003) and consumed billions of dollars, genome sequencing nowadays can be done in a day for only $1,000. Oxford Nanopore Technologies even plans to sell a genome sequencer as big as a USB drive for $900 before the end of the year. With the prevalence of genome sequencing increasing, concerns are rising once again about who should own genetic information and how it should be handled. These anxieties have compelled the government to return to these bioethics issues. The Commission for the Study of Bioethical Issues, an advisory committee commissioned by President Obama in 2009, plans to submit a report by the end of the year detailing its thoughts on these issues.
But how will they address these concerns? In a federal document, the Commission referenced the “integration of large-scale human genome sequencing into research and clinical care” while also maintaining a balance between “individual and societal interests.” The clause of individual and societal interests suggests that the government will try to protect privacy rights of individuals, but that the integration of genetic information into clinical research is also possible. It will be interesting to see how the government perceives this revolution in health care: will it hinder it or let it grow?
- Hwang D, Lee IY, Yoo H, Gehlenborg N, Cho JH, Petritis B, Baxter D, Pitstick R, Young R, Spicer D, Price ND, Hohmann JG, Dearmond SJ, Carlson GA, Hood LE. A systems approach to prion disease. Mol Syst Biol. 2009;5:252. Epub 2009 Mar 24. PubMed PMID: 19308092; PubMed Central PMCID: PMC2671916.
- Johnson, Jeremy. “All Hope Is Not Lost for Better Healthcare.” Institute for Systems Biology. Institute for Systems Biology, 17 Feb. 2012. Web. 13 May 2012.
- Wayne, Alex. “DNA Mapped in a Day Prompts U.S. Review of Genome Ethics.”Bloomberg.com. Bloomberg, 26 Mar. 2012. Web. 13 May 2012.
- Tian Q, Price ND, Hood L. Systems cancer medicine: towards realization of predictive, preventive, personalized and participatory (P4) medicine. J Intern Med. 2012 Feb;271(2):111-21. doi: 10.1111/j.1365-2796.2011.02498.x. Review. PubMed PMID: 22142401.
- United States. Department of Health and Human Services. Office of the Federal Register. Request for Comments on Issues of Privacy and Access With Regard to Human Genome Sequence Data. By Wanda Jones. Federal Register. Web. 13 May 2012.
- Image credit (public domain): National Human Genome Research Institute. “ATCG.” Wikimedia Commons. 9 Dec 2009.