The discovery of DNA sequencing has been hailed as one of the most fascinating stories of the last 100 years. Three major events, occurring within the last 100 years, are considered the backbone of the story: the the rediscovery of Mendelism and the laws of heredity in 1900, the discovery of the DNA structure in 1953, and the publication of the first draft of the complete human genome (published in 2001).
Albrecht Kossel successfully proved the existence of both DNA and RNA, although at the time they had two very different names. DNA was called thymonucleic acid, while RNA was known as yeast nucleic acid. Kossel, a leading scientist and chemist at the time, successfully proved pentose sugar was a part of the yeast nucleic acid. In 1910 he was awarded the Nobel Prize for his work on the chemistry of nucleic acids.[1]
Another brilliant mind of the day, Phoebus Levene worked directly under Kossel. A highly respected chemist himself, Levene identified the pentose sugar found in yeast nucleic acid as ribose in 1909. Since then, the yeast nucleic acid has been known as ribonucleic acid, or RNA.
It took almost 20 years for Levene to isolate pentose sugar in thymonucleic acid. When it was finally identified in 1929, it was identified as 2-deoxyribose by Levene and his colleagues. From that point on, thymonucleic acid was known as deoxyribonucleic acid or DNA.
James Watson and Francis Crick, two students at Rockefeller University, discovered and solved the DNA structure in 1953 while visiting King’s College London. During the next three decades, the fundamental principles of molecular gene structure, expression, and function were explored and discovered.
In 1984, a symposium was sponsored by the US Department of Energy called the Alta Summit. This meeting is credited for bringing together a handful of scientists who believed that the mysteries of life – as well as revolutionary advancements of medical sciences – could be achieved if the human genome was sequenced. What they didn’t know was that the human genome would be successfully sequenced within the next 15 years.
Sequencing Your Own Genome
Many websites now offer the option to the public for a fee. Back in 2001, when the first draft of human sequencing was published, it took 13 years and cost $2.7 billion. Now, it is no longer a matter of science fiction to map DNA “at home” – nor does it cost billions of dollars. Certain private companies offer sequencing for as little as $100 using buccal swab kits. For a more thorough return, private consumers can expect to pay roughly around $1000.[2]
What Can You Do with Your Genetic Testing Results?
The information discoverable from this sequencing can vary, and depends on the type of service chosen. While many companies perform this service to offer medical insight, others connect consumers with possible living ancestors and extended family members.
There are numerous services available to interpret genetic information. One of the most common includes locating ancestral matches and other tools for analyzing raw data such as an X-DNA Relationship Path Finder, Autosomal Segment Analyzer, a DNA Cleaner, and an SNP Extractor. There are even tools capable of approximating where a persona’s ancestors came from. Most of these are Internet-based and can be accessed with simple browser extensions.[3]
The More You Know…For Better or For Worse?
Genome sequencing appears to be the doorway to the age of personalized medicine. The more consumers know about their bodies and their medical history, the more accurate medical treatment can be.
Mapping the human genome also opens the doors for preventative medicine. As early as 1990, screening infants for Phenylketonuria (PKU) had already proven successful using genetic mapping. By genetically screening infants for PKU, doctors were able to successfully identify those with PKU long before children became symptomatic. The treatment began at infancy by merely altering the diets of PKU-positive babies, and ultimately proved successful in preventing the onset of the disease.[4]
Other cases demonstrate how high density genetic mapping can identify susceptibility loci for rheumatoid arthritis. The study successfully illustrates the advantages of dense SNP mapping analysis in favor of genetic mapping.[5]
In these instances, the case can be made in favor of information. The patients whose illnesses have been prevented thanks to genome mapping would likely agree that having such information changes and improves lives.
Others remain less convinced. As genome sequencing grows in popularity, there is increasing concern that such information may be used against patients in the future. Some feel that genetic screening can be used to discriminate against certain demographics, particularly those with pre-existing conditions. Insurance companies allowed to access this information may be able single out those with a high risk of a disease and assign higher premiums or deny insurance coverage altogether. Employers might use genetic information as a basis for hiring decisions. Others believe that reproductive decisions will be made based on genetic mapping.
With these factors in mind, it is important to note that like all scientific discoveries, genome sequencing comes with a cost: knowledge. What mankind does with such knowledge will be determined in time.
No Longer Just Science Fiction
Some have compared genome mapping to early chemotherapy techniques, and questioned where sequencing will lead the medical community in years to come. Eric J. Topol, an American cardiologist, geneticist, and digital medicine researcher, posed such a question in 2013, at a summit for genetic research in California. He suggested, “Chemotherapy is just medieval. It is such a blunt instrument. We are going to look back on it like we do the Dark Ages.” [6]
Chemotherapy, literally meaning “chemical therapy,” began initially as a form of chemical warfare in 1940s with the use of nitrogen mustard gas. Today, it is used as an aggressive treatment to kill rapidly growing cancerous cells. The early discovery and use of nitrogen mustard gas as chemotherapy was met with derision and fear. Yet today chemotherapy is a widely recognized and administered treatment for many cancers.
This comparison suggests that any scientific discovery has potential to be both harmful and helpful, depending on its usage. What we do know is that the ability to map out a person’s genetic potential opens the door to the age of personalized medicine. With regard to genome sequencing, the scientific and medical community recognize that by using information in a patient’s personal genome, it is now possible for geneticists to tailor medical treatment to individual diseases and patients. Each person’s genome offers information that can predict predispositions for numerous health concerns. These discoveries can help predict medical issues, detect diseases or even prevent allergic reactions.
Doctors know a lot when it comes to the human body, but there is still much to learn. While all people share certain physical characteristics, individuals respond differently to various stimuli and medical treatments. By mapping genetic information, it may be possible to receive – with significant accuracy – personalized medical care that was previously considered just ‘science fiction.’
References
[1] Human Genome Project Information Archive | Human Genome Project
https://web.ornl.gov/sci/techresources/Human_Genome/project/hgp.shtml
[2] 5 Services That Will Sequence Your DNA | Mashable Lifestyle
http://mashable.com/2013/05/15/personal-genetics-resources/
[3] What Else Can I Do With My DNA Test Results? | The Genetic Genealogist
http://www.thegeneticgenealogist.com/2013/09/22/what-else-can-i-do-with-my-dna-test-results/
[4] The Ethical Considerations of Genetic Screening | North Dakota State University
https://www.ndsu.edu/pubweb/~mcclean/plsc431/students98/christenson.htm
[5] High-density genetic mapping identifies new susceptibility loci for rheumatoid arthritis | Nature Genetics
http://www.nature.com/ng/journal/v44/n12/full/ng.2462.html
[6] What happened when I had my genome sequenced | The Observer via The Guardian
http://www.theguardian.com/science/2013/jun/08/genome-sequenced