Personal Genetics 101 (7)
Personal genome sequencing assesses the status of all of your genes at one time, just as if the Human Genome Project were conducted specifically on you.
The completion of the Human Genome Project was a great advance for medical research, providing us with part of the blueprint that makes us human. However, the DNA sequence produced by the Human Genome Project is not identical to yours; virtually every individual on the planet carries a unique set of variations in their DNA sequence, affecting their outward appearance, their behavior, and from a medical standpoint, their susceptibility to disease.
An ever-growing list of genetic tests are available to look for known genetic mutations that are associated with specific diseases. Genetic tests usually characterize only one gene (or just specific parts of one gene), and the availability of such genetic tests depends on the ability of scientists to link well-characterized diseases to particular genes. For conditions with specific genetic causes, such as Huntington’s disease or cystic fibrosis, these tests have proven to be relatively straightforward. In contrast, progress has been more challenging with respect to predicting a person’s risk for complex and multifactorial diseases, such as diabetes and heart disease.
An analysis of your entire genome would not only assess genes that are implicated in disease, but could also reveal information about your physical traits, your behavior, and even your ancestry. In addition, this assessment would include portions of the genome that are not yet well understood, including genes whose function is not yet known. As its stands today, only the information from the parts of your genome that are well understood might benefit your present health care choices. However, as more and more people are sequenced, scientists will be provided with a larger set of data from which to learn about the poorly understood regions of the genome and their functions, including relationships to diseases. This is one potential benefit to health care consumers in the future (see Genotype and phenotype). In some ways, widespread personal genome sequencing may blur the line between medical practice and biomedical research. (Importantly, your genome is dynamic and only part of the story. Click here to learn more.)
The technology that made the Human Genome Project possible is plummeting in cost, and as a result, genetic analysis is increasingly available to a broader population. The first sequence of the human genome was achieved with hundreds of sequencing machines working for years. Now a single machine can sequence a full human genome in a matter of days. (Note, the analysis takes much longer than the actual process of sequencing.) To make the sequencing technology more accessible, there has also been a push to make sequencing machines smaller and more affordable. For example, some companies are developing sequencing machines that are the size of a loaf of bread or even a bar of soap. In 2014, companies continue to compete to bring the cost of sequencing a human genome to $1,000 (US). Sequencing a person’s genome has already found clinical applications, particularly in the diagnosis of rare childhood conditions and informing cancer therapeutics. In the coming years, perhaps reading human genomes might become a routine tool for preventative medicine as well and might be carried out in your doctor’s office.
Ultimately, the application of genomic information could enhance our ability to make informed and appropriate decisions regarding health care, including, for example, the treatment of specific diseases or predispositions and the choice of drugs and drug dosage. At the same time, the questions it raises, and the possible unforeseen medical and social consequences, are yet to be fully explored. This advent of “personal genetics” will bring novel challenges and extensive questions on the ethical, legal and social issues (ELSI) that we, as a society and as individuals, need to address.
Join the conversation!
Check out the videos below to hear our friends and colleagues weigh in on why it is important to take part in the conversation about the future of personal genetics. Then, stay in touch by liking pgEd on Facebook, following us on Twitter, or joining our mailing list.
Your genotype is your complete heritable genetic identity; it is your unique genome that would be revealed by personal genome sequencing. However, the word genotype can also refer just to a particular gene or set of genes carried by an individual. For example, if you carry a mutation that is linked to diabetes, you may refer to your genotype just with respect to this mutation without consideration of all the other gene variants that your may carry.
In contrast, your phenotype is a description of your actual physical characteristics. This includes straightforward visible characteristics like your height and eye color, but also your overall health, your disease history, and even your behavior and general disposition. Do you gain weight easily? Are you anxious or calm? Do you like cats? These are all ways in which you present yourself to the world, and as such are considered phenotypes. However, not all phenotypes are a direct result of your genotype; chances are that your personal disposition to cats is the result of your life’s experience with pets rather than a mutation in a hypothetical cat fancier gene.
Most phenotypes are influenced by both your genotype and by the unique circumstances in which you have lived your life, including everything that has ever happened to you. We often refer to these two inputs as “nature,” the unique genome you carry, and “nurture,” the environment in which you have lived your life.
Answer 5 questions about genetics and pin yourself on our world map. Will you be the first in your neighborhood? Take 5 minutes and find out!
The unique code of DNA you were born with (your personal genome) affects your health, appearance, and many other traits that make you unique. However, that is only part of the story. Your genome is dynamic over the course of your lifetime. Consider the following:
(1) There are trillions of bacteria, viruses, and yeast and other fungi (collectively called microbes) that live in and on your body. The DNA from all the microbes on your body is called your microbiome, and genes from these microbes outnumber your own roughly 300 to 1! The make-up of your microbiome can affect your health, your digestion, and maybe even your mood. Your microbiome is ever-changing, influenced by the foods you eat, the people you kiss, the surfaces you touch, your use of antibiotics and sanitizers, and more.
(2) Mutations are simply changes in one’s DNA sequence and are not necessarily bad or good. Mutations can arise when a cell makes a mistake copying its DNA or upon exposure to environmental insults, such as UV rays or certain chemicals. When a mutation arises in a cell, the DNA in that cell is then slightly different from the DNA in the neighboring cell, and this is called mosaicism. When the cell divides, it will pass on the mutation to its descendants. (Note: only certain cells in our bodies can give rise to egg and sperm. Therefore, a mutation that arises in a cell in your big toe will not be passed down to your children.)
(3) Some people carry genetically distinct cells that originate from another individual. This phenomenon, called chimerism, can arise in people who have received bone marrow transplants or women who have carried a pregnancy.
In addition, personal genetics reflects the influences of our environment, lifestyle, and social experiences on how our genes work (epigenetics). There is even evidence suggesting that these influences can be passed down from one generation to the next (so-called transgenerational epigenetic inheritance).
As a result, our genes are only part of a much more complex story of who we are and what our future holds. The growing field of personal genetics is at the intersection of science and society; it is both an exploration into the complex interactions through which our genes and our environment influence our physical, mental and behavioral states as well as an on-going conversation on the meaning for individuals and society.
Technological developments are making it possible to read a person’s entire genetic code, or genome, more rapidly and at a lower cost than ever before. Personal genome sequencing is allowing scientists and doctors to better understand the connections between genes and human health, improve medical care and help extend people’s lives. As the cost of genetic analysis decreases and research advances, it is becoming increasingly possible to include a person’s genetic make-up in the repertoire of tools that inform his or her healthcare.
Currently, having your genome sequenced would be similar to having thousands of genetic tests done at the same time – you would learn quite a bit about your genetic make-up, but the information that would be gleaned from your sequence would be limited to the parts of the genome that are already well understood. However, if many people have their DNA sequenced and provide their medical history as well as a detailed physical description of themselves, personal genome sequencing could be a powerful tool for learning more about the parts of the genome that are poorly understood.
Essentially, the power of sequencing comes from the exercise of comparing genotype and phenotype; by analyzing the genomic sequences (genotypes) and physical characteristics (phenotypes) of millions of people, personal genome sequencing has the potential to link specific traits to specific genes. The most obvious benefit of these analyses will be to better understand the interplay of nature and nurture in known diseases, with the hope that they would lead to better treatments, cures, preventative measures, and healthier generations of children.
Notably, the field of pharmacogenomics is one area where there have already been many successes. Our DNA can impact how we respond to certain drugs as well as how rapidly our bodies break drugs down. The goal is to use information about a person’s genetic make-up to identify medications that will be most effective with minimal side effects.
Recently, there have been several examples where genome sequencing has resulted in both a diagnosis and treatment plan of a patient. “One in a billion: A boy’s life, a medical mystery,” written by Mark Gallagher and Katherine Gallagher, describes many of the scientific and personal issues that underlie the emerging field of medical sequencing.
Physicians and personal genomes
Doctors will be faced with many questions as personal genome sequencing drops in cost and interest in genetics increases. Furthermore, a recent study conducted in the United States shows that a large majority of the population is willing to participate in studies about genes, the environment, and health.
In this time when the promises of personalized medicine outpace some of the realities in the clinic, physicians will increasingly be managing expectations of patients and interpreting the latest scientific discoveries and policy guidelines issued from insurers.
pgEd is in the process of developing a short list of papers that we hope will give doctors and other medical professionals a baseline understanding of the issues and serve as a jumping off point for more in depth reading. We also recommend the Genetics and Genomics for Health Professionals resource created by the NHGRI. resources that have been created at the Beth Israel Deaconess Medical Center’s Genomic Medicine Initiative. Dr. Eric Topol’s excellent book, The Creative Destruction of Medicine, is another resource pgEd recommends for healthcare workers and anyone who is interested in a look at how technology , and an embrace of the changes innovation can bring, could transform health and the healthcare community.
Personal genome sequencing is uncharted waters in our society. The benefits and risks of sequencing are likely to be connected, complex, and largely unknowable until years have passed and the consequences are examined across several generations. However, thinking through the issues surrounding personal genomics now, rather than later, may help to avoid potential pitfalls and ensure that the good outweighs the bad.
The benefits of sequencing may be mostly in the medical arena. In the long term, sequencing of many individuals could provide new information on the genetic basis of poorly understood diseases, with the potential to provide new therapies. However, there may also be immediate benefits based on our current understanding of genetics and health. Knowledge of elevated risks for known diseases could allow you to make proactive decisions about your health; visiting the doctor for more frequent check ups or screenings, choosing one type of prescription drug over another based on your metabolism, altering your diet or exercise plan, informing reproductive decisions, or making certain kinds of arrangements for your future medical care are all ways that you might use the information that you learn from your sequence. This individualized avenue of health care is often referred to as “personalized medicine.”
In addition to medical benefits, some believe that the advent of widespread sequencing could foster new connections among different people or groups. For example, people with shared genetic variants and mutations may wish to contact one another in order to discuss their common experiences, just as people living with debilitating diseases do currently (Facebook is host to many groups of people sharing information and seeking support for conditions like Huntington’s Disease, BRCA mutations, and macular degeneration, to name just a few).
Unintended consequences: privacy
The possibility of benefits also comes with potential for harm, unintended consequences, and the altering of how we think about a number of cultural, personal, and biological issues.
Personal sequencing will likely impact our concept of personal privacy, as the technology may allow for the possible exposure our unique “code” that we leave behind on every surface we touch. In particular, even if databases storing our personal sequences are protected from the public eye, the DNA that one may discard on a used coffee cup could eventually be used to identify an individual’s physical characteristics, including race, height, facial structure, and one’s susceptibility to genetic diseases. This will likely have enormous implications for the criminal justice system, which generally seeks to increase the availability of DNA samples from the population.
Fear of genetic discrimination
In addition, there is a fear that information about your probable health care needs may affect your ability to find employment or insurance. The passage of the Genetic Information Nondiscrimination Act (GINA) in 2008, which forbids the use of genetic information in employment and the ability to obtain and set fees for health insurance, is a major milestone in the United States. The hope is that GINA will not only prevent genetic discrimination but also encourage greater participation in medical research. To learn more about genetic discrimination and GINA, click here. Also, the Genetics and Public Policy Center has developed a comprehensive resource about GINA for multiple audiences ranging from the general public to health care professionals.
Benefits, impacts, and complexities – Spotlight on PGD
Questions abound in the areas of privacy, autonomy, and whether or not government regulation is necessary in the field of personal genetics. Take, for example, the procedure known as preimplantation genetic diagnosis (PGD). Embryos, created via in vitro fertilization (IVF), can now be tested for a number of genetic traits. The results can help prospective parents choose which embryo(s) to implant in a woman’s uterus. Thousands of the children in the United States have already been born as a result of this process. PGD is most commonly used to assess chromosomal characteristics or the presence of a mutation that is linked to an often fatal childhood disease. However, in time, sequencing technology could be used on an embryo as it could be on an adult human, giving prospective parents an enormous amount of information. This information could be a comfort and a relief in some situations but a source of worry for them and their child in other situations.
Questions and conversations for the future
Clearly the scope of these issues is enormous, and one can argue that the potential for harm reaches beyond the ability of our societal structure to guarantee protection of individual rights. As such, it would be wise to step back and examine the big picture before we embark on our journey toward a genomic future: Who has the most to gain and the most to lose? Who bears the most risk? Where do we draw the line? And who exactly gets to draw that line, and with what authority? Genome sequencing has great potential to improve health, create new treatments and bring about cures for disease – so how do we make sure those possibilities can be realized and minimize the risk at the same time?
Want to keep exploring?
These are exactly the kinds of conversations that pgEd seeks to encourage. There is no right answer and the only guarantee is that people will hold a broad range of opinions. Check out some of our other resources (lesson plans, blog, videos, and more) and join the conversation!
If you looking to explore the many personal and social issues related to sequencing, or are considering volunteering for a genome sequencing research study or purchasing some form of genome analysis, here are a few questions you might ask yourself:
- How much information do I want about my risks for disease? Will I learn other things I wasn’t expecting?
- What information do I want to share, and with whom?
- What might I learn that is both exciting and maybe surprising about my ancestry?
- What roles do environment and lifestyle play in my personal traits?
- How much do my genes really reveal about me?
- How will my relatives feel about the information learned, as it could also impact them?
- Should I share information with my health, life, and long-term disability insurers?
- What, if any, sort of proactive decisions regarding lifestyle or medical choices should I make? Can I afford the treatments I might want or need?
- Who owns my DNA, and the information contained within it?
- Could this change how I think about myself, culturally, physically, emotionally?
- What might some of the unintended consequences be for me, my family, and society?
The stakeholders in this technology, beyond the academic and corporate researchers involved with the scientific challenges, are numerous. Doctors, lawyers, policy makers, drug companies, public health agencies, elected officials, privacy advocates, insurers of all kinds, parents, teachers, children, law enforcement and many others will face new possibilities and challenges as a result of personal genome sequencing.
But the most important stakeholder is you. Personal sequencing will provide individuals with unprecedented knowledge and access to their own genetic information. By becoming a more active and informed health care consumers, comes to the power to transform and hopefully improve medicine.
Resource Center (2)
pgEd is compiling a list of books about genetics, bioethics, and science and society, which was started by the GETed 2013 attendees. Drop us a note to add your favorite book to the list.
- The Seedling Stars by James Blish
- Long for this World by Michael Byers
- Intuition by Allegra Goodman
- Wool Omnibus by Hugh Howey
- Tainted Blood (A Reykjavik Murder Mystery) by Arnaldur Indridason
- Mendel’s Dwarf by Simon Mawer
- Time Traveler’s Wife by Audrey Niffenegger
- The Jenna Fox Chronicles by Mary Pearson
- Second Glance by Jodi Picoult
- Sing You Home by Jodi Picoult
- Unwind Collection by Neal Shusterman
- The Chrysalids by John Wyndham
- Here is a Human Being: At the Dawn of Personal Genomics by Misha Angrist
- Design in Nature: How the Constructional Law Governs Evolution in Biology, Physics, Technology and Social Organization by Adrian Bejan and J. Peder Zane
- Missing Microbes: How the Overuse of Antibiotics Is Fueling Our Modern Plagues by Martin Blaser
- When Will Broccoli Taste Like Chocolate?: Your Questions on Genetic Traits Answered by Stanford University Scientists by Dale Bodian and D. Barry Starr
- On the Origin of Stories: Evolution, Cognition and Fiction by Brian Boyd
- The Cure For Everything: Untangling Twisted Messages about Health, Fitness and Happiness by Timothy Caulfield
- The Language of God: A Scientist Presents Evidence for Belief by Francis Collins
- The Science of Human Perfection: How Genes Became the Heart of American Medicine by Nathaniel Comfort
- The $1000 Genome: The Revolution in DNA Sequencing and the New Era of Personalized Medicine by Kevin Davies
- The Sports Gene: Inside the Science of Extraordinary Athletic Performance by David Epstein
- My Beautiful Genome: Discovering Our Genetic Future, One Quirk at a Time by Lone Frank
- The Storytelling Animal: How Stories Make Us Human by Jonathan Gottschall
- Made to Stick: Why Some Ideas Survive and Others Die by Chip Heath and Dan Heath
- The Fifth Branch: Science Advisors as Policymakers by Sheila Jasanoff
- The Ghost Map: The Story of London’s Most Terrifying Epidemic by Steven Johnson
- The Forever Fix: Gene Therapy and the Boy Who Saved It by Ricki Lewis
- The Black Stork: Eugenics and the Death of “Defective” Babies in American Medicine and Motion Pictures since 1915 by Martin Pernick
- Sex, Love and DNA: What Molecular Biology Teaches Us About Being Human by Peter Schattner
- The Immortal Life of Henrietta Lacks by Rebecca Skloot
- Far From the Tree by Andrew Solomon
- Telling Genes: The Story of Genetic Counseling in America by Alexandra Minna Stern
- The Seven Daughters of Eve: The Science That Reveals our Genetic Ancestry by Bryan Sykes
Have a suggestion?
Thanks to an energetic session at GETed 2013, pgEd has compiled a list of resources, websites and projects contributed by a number of the participants. We are using this page to share these resources and create a living, breathing document to which we invite you to contribute. These include educational tools for teachers, games and apps, museum exhibitions, culturally-relevant resources for communities, popular websites for increasing dissemination, as well as resources related to health, policy, and entertainment.
American Society of Human Genetics (via Mike Dougherty, ASHG):
– Science careers mapped out in an interactive flowchart
– Lesson plans from the Geneticist-Educator Network of Alliances
– Darwin Day and educational materials on evolution
BioQUEST Curriculum Consortium (via Linda Grisham, MassBay Community College)
– Calendar of workshops, including June, 2013 workshop on using data in the classroom
– Archives of prior projects, including cases related to genomics
DNA Learning Center (via Dave Micklos, DNA Learning Center, Cold Spring Harbor Laboratory)
– Educational, lab, and bioinformatics websites
– History of eugenics, including the Image Archive on the American Eugenics Movement, the DNA Interactive Chronicle, and an article that Dave co-authored entitled “Engineering American society: the lesson of eugenics.”
Genentech’s “Ralph’s Killer Muenster” (via Dana Waring, pgEd)
– Free iPad app to engage and inspire a broader audience through genetics-based puzzles
Genetic Counseling Cultural Competence Toolkit (via Samantha Baxter, National Society of Genetic Counselors)
Genetics and Literature, an interdisciplinary course (via Jay Clayton, Vanderbilt University)
Hawai’i Department of Health Genetics Program Teacher Resource Kit (via Marnie Gelbart, pgEd)
Hollywood, Health & Society (via Sandra de Castro Buffington, HHS)
HudsonAlpha’s digital education resources (via Chris Gunter, Girlscientist Consulting)
– The Progress of Science timeline
– Genome Cache, free iPad app and interactive learning module
– iCell, free iPad app that invites users to explore the inside of a cell
Literature, Film, and Genetics (via Jay Clayton, Vanderbilt University)
MacArthur Foundation Research Network on Law and Neuroscience blog (via Tracy Gunter, Indiana University School of Medicine)
MadSci Network (via Paul Szauter, University of New Mexico)
– Interactive question & answer website featuring an “Ask-An-Expert” service
Northwest Association for Biomedical Research (via Jeanne Chowning, NWABR)
– Lesson plans to promote understanding of biomedical research and ethics through dialog, ranging from Bioethics 101 to Advanced Bioinformatics
– Bio Expo students have produced videos about Crohn’s Disease, Gene Therapy and a Transgenic Salmon Shop
NOVA’s “Cracking Your Genetic Code” video (via Dana Waring, pgEd)
Paul Szauter’s Movie Project, in development (via Paul Szauter, University of New Mexico)
– Reviews based on scientific and ELSI content
Personal Genetics Education Project (via Dana Waring and Marnie Gelbart, pgEd)
– Current Genetics Update, new weekly blog feature
– Map-Ed, pin yourself on a global map after answering 5 questions on core concepts in genetics
Pinterest as a site for dissemination (via Belen Hurle, NHGRI)
– Boards with lesson plans for high school students
– Curating searchable collections on internet
Primer on Genetics and the Brain at The Dana Foundation (via Tracy Gunter, Indiana University School of Medicine)
Proteopedia (via Shannon Colton from the Center for BioMolecular Modeling)
– 3D encyclopedia for all entries in the Protein Data Bank
ReGenesis (via Tom Chehak, executive producer)
– Canadian television series (2004-2008) with gaming-themed companion website and website that reviews the real science behind each episode
Science in the News (via Marnie Gelbart, pgEd)
– Harvard graduate student organization that features an on-line news resource and videotaped presentations
Smithsonian’s new exhibit “Genome: Unlocking Life’s Code” created in partnership with the National Human Genome Research Institute (via Belen Hurle, NHGRI)
– At Smithsonian until Sept, 2014 and then it will travel for four years
– Educational resources on companion website
Thomas.gov (via Ed Ramos, NIH)
– Search engine for federal legislation
Useful Genetics (via Rosie Redfield, University of British Columbia)
– A free online college-level genetics course offered on the Coursera platform and open to anyone; it puts more emphasis on relevance than on classical genetic analysis.
Visual Literacy and the Periodic Table (via Linda Grisham, Mass Bay Community College)
Wikipedia needs editing! (via Madeleine Price Ball, Personal Genome Project)
– With an enormous daily audience (the Genetics page gets approximately 2,200 views a day), the MAOA page might be a good starting point!
Youreka Science (via Marnie Gelbart, pgEd)
– Collection of short videos explaining recent biomedical findings
23andMe’s message boards (via Paul Szauter, University of New Mexico)
– A useful resource (accessible only by 23andMe subscribers under “Research & Community/Community”) to get a sense of where people are at with respect to personal genetics
Want to add to the list?
Do you have another resource to add to the list? Has something new come along that you believe is of interest? Please use this form below to submit your resource to the collection (all fields are required). (Note: Your email address will not be posted on-line.)
Topics in personal genetics (5)
Several years ago, a small number of companies in the United States began selling DNA testing kits directly to consumers (referred to as DTC) via the internet. This market was made possible, in part, by the decreasing costs of genome analysis. In 2014, DTC testing generally does not produce a full genome sequence, like the Human Genome Project; rather, companies often look at sites in the genome that commonly differ between individuals, known as single nucleotide polymorphisms (SNPs). Companies offer a broad array of tests that report on a person’s ancestry and health, as well as a number of other traits. Examples range from a person’s ability to taste bitter flavors or the photic sneeze reflex (uncontrollable sneezing when exposed to bright light) to risk for developing heart disease or diabetes.
The DTC debate
Should people be able to access their genetic information directly from a company? (more…)
The role of genetic testing in sports continues to grow as technology evolves and as coaches, players, and parents ask themselves “Can my DNA provide me with information relevant to my sport?” As the genetic factors underlying many health conditions are better understood, some doctors, coaches, and academic and athletic organizations are wondering whether genetic analysis can provide health and safety benefits for athletes. Can genetic data help minimize the risk of injury? In addition, as scientists uncover numerous genes with links to athletic performance, questions have emerged about whether genetics might play a role in guiding young people toward the sport in which they are likely to have the most success. (These questions are also explored in our lessons “Athletics and genetics“and “Protecting athletes with genetic conditions: Sickle cell trait.”) The debate about the science and ethics continues.
Sickle cell trait and college athletes – universal screening?
In the United States, all college athletes in the National Collegiate Athletic Association (NCAA) are tested for the genetic condition sickle cell trait (SCT). Often, people with SCT do not experience any symptoms, but are at increased risk for health problems and even death under certain conditions, such as intense exercise. Several young men have died in the course of sports practices or games from complications related to SCT. Out of an abundance of caution, National Football League player, Ryan Clark, diagnosed with SCT as a child, no longer plays in games at Mile High Stadium in Denver, after becoming severely ill during a 2007 game at high altitude. Following a lawsuit, the National Collegiate Athletic Association (NCAA) began screening all of its athletes for SCT in hopes that universal screening will save lives by making student athletes with SCT and their coaches more aware of the risks and preventative measures. Critics argue that the most effective way to prevent death is not through testing, but rather through improved safety conditions and awareness of dehydration, the dangers of practicing in extreme heat, and muscle exhaustion, which would benefit all players regardless of their genetic profile.
Hypertrophic cardiomyopathy – who should be tested?
In a related discussion, some doctors and athletic groups are advocating that all young people playing high-intensity sports, such as soccer and basketball, be screened for a dangerous heart condition called hypertrophic cardiomyopathy (HCM). HCM, a thickening of the heart muscle, is a leading cause of sudden cardiac death in young athletes in the United States. HCM can be detected via a number of physiological tests, including electrocardiogram (ECG). HCM can be caused by mutations in any one of over a dozen genes, making genetic diagnosis relatively complex.
HCM often first presents when a young athlete collapses and dies on an athletic field. Some doctors, parents, and advocates believe all athletes should be screened for HCM as standard practice for participation in all endurance or high-energy sports. People with HCM are advised not to play high-intensity sports and, in one region in Italy, where children are screened by ECG early in their teenage years, a drop in HCM death rates has been observed. Many believe testing for HCM will save lives, in part by identifying children most at risk and excluding them from high-intensity sports.
The controversy over HCM testing in athletes stems from concerns that population-wide screening for a relatively rare disease would be costly and inefficient. The prevalence of HCM in adults is roughly 1 in 500. Practical and philosophical questions persist about whether to seek out medical information that, on one hand, might limit a significant number of children’s opportunity to play sports, but which would likely prevent young adults with HCM from dying as a result of their athletic endeavors.
Is there a “sports gene”?
Several individual genes are frequently mentioned when talking about “sports genes.” ACTN3 is linked to muscle contraction and, more broadly, sprinting ability. ACE is another well-studied gene though to influence athletic performance, and COL5A1 and other related genes tied to collagen production may have some impact on soft tissue injury risk. Preliminary studies have shown that the APOE gene, which has a well-established link to Alzheimer’s disease, may also impact how a person recovers from concussion.
People are increasingly able to learn about their genetic make-up in the context of sports performance and injury prevention. Questions remain about how practical this information might be to a player, coach, or parent as a single gene or group of genes are unlikely to be responsible for an individual’s athletic talents. It is unlikely that a genetic profile favoring explosive, fast twitch muscle fibers are all one needs to make it to the Olympics in the 100 meter race – training, lung capacity, bone and muscle profiles, how effectively one’s body can shuttle oxygen around, as well as culture and environment are also part of the puzzle. Even a trait like height, which might seem pretty simple to understand, involves at least 120 genes or clusters of genes and can be highly influenced by environment, nutrition, and other factors. As slam-dunk champion and NBA star Nate Robinson reminds us, having the “right” mix of genetic and environmental influences to succeed in sports isn’t always necessary. In a league where the average player is about 6’7” and many players topping 7 feet tall, Robinson is a stand out player at only 5’9”. Environmental and genetic influences of complicated human traits, like athleticism, are not easily disentangled.
Understanding probability and risk and making sense of genetic testing
The E4 version of the APOE gene has been linked to an elevated risk for Alzheimer’s disease and, more preliminarily, to a poorer recovery from concussion. With companies offering tests to assess a person’s risk for difficult recovery from a concussion, there is much debate about the responsibility for educating consumers on the well-established link to Alzheimer’s risk. Many players or parents might be interested in a genetic test that helps predict concussion outcomes, but might think twice about testing their 10-year-old hockey or football player if the test could also uncover an elevated risk for Alzheimer’s disease, a degenerative neurological conditions currently without a proven treatment or cure. This example highlights the question of how to make decisions based on information that may be preliminary, as research continues to explore the possible link between APOE and concussions, or uncertain, as the APOE test is partially predictive for Alzheimer’s disease. This is because a person with two copies of APOE-E4 is more likely than average to develop Alzheimer’s, but will not necessarily develop the disease. Thus, sports and genetics analysis is also a way to think about the predictive value of genetic information and the concept of likelihood or risk. Knowing one’s genetic information and understanding risk could be beneficial for informing lifestyle and healthcare choices as well as future planning.
- “Surprise Marfan Syndrome diagnosis halts an athlete’s path to the NBA,” June 2014, pgEd Blog.
- David Epstein’s 2013 book “The Sports Gene” is an excellent read for a detailed discussion on athletics and genetics. Reeves Wiedman’s review in The New Yorker gives a succinct summary of Epstein’s key themes.
- “Hidden threats to young athletes,” May 2013, by Bill Pennington, New York Times.
- “Insurance coverage, medical costs and genetic testing,” July 2012, pgEd Blog.
- “Born to Run? Little Ones Get Test for Sports Gene,” November 2008, by Juliet Macur, New York Times.
Personalized medicine, also referred to as precision medicine, holds great promise to improve healthcare. According to the National Cancer Institute, personalized medicine integrates “information about a person’s genes, proteins, and environment to prevent, diagnose, and treat disease.” As the cost of genetic analysis decreases and research advances, it is becoming increasingly possible to include a person’s genetic make-up in the repertoire of tools that inform his or her healthcare. Personal genome sequencing has been used to diagnose children with rare conditions when other approaches have failed and has been applied in efforts to predict a person’s susceptibility to a medical condition. In addition, a growing number of medications are prescribed based on a person’s genetic make-up.
The stories of Nic Volker and the Beery twins have garnered much attention about the potential for personal genome sequencing to advance healthcare. Nic Volker is the first child to receive a diagnosis and successful treatment as a result of genome sequencing. Nic, now thriving, had been terribly sick with a rare, undiagnosed medical condition and endured over one hundred surgeries by age 4. A portion of Nic’s genome was sequenced to look for a genetic mutation that caused his illness, which led to a diagnosis and pointed doctors towards a treatment. The Beery twins, Noah and Alexis, were misdiagnosed with cerebral palsy as babies. Years of medical treatments, mysterious symptoms and a search for answers ensued. After having their genomes sequenced as teenagers, they were accurately diagnosed and successfully treated.
How might personalized medicine change how drugs are prescribed? What is pharmacogenomics?
A major goal of personalized medicine is to tailor treatments, using a person’s genetic make-up to identify medications that will be most effective with minimal side effects. Traditionally, doctors prescribe a medication and then wait to see how the patient responds; some will respond positively, some will not respond at all, and some will have a negative reaction and suffer side effects. It is estimated that nearly 70% of Americans take at least one prescription medicine, and there are many questions about the risks of medications that are overprescribed, underused or given to people for whom the drug is not working as hoped.
The field of pharmacogenomics is exploring how people’s genes impact their response to medications. According to the National Institutes of Health’s Genetics Home Reference, “this relatively new field combines pharmacology (the science of drugs) and genomics (the study of genes and their functions) to develop effective, safe medications and doses that will be tailored to a person’s genetic makeup.” A number of drugs, including those that can treat HIV, cystic fibrosis, depression and a number of types of cancer, have pharmacogenomic information in their label regarding an individual’s genetic make-up. With genetic testing before treatment, people may avoid medications that will cause harm or be ineffective, and hopefully find the drug that will most effectively treat their illness.
In some cases, drugs are intended only for people with a specific genetic make-up. Kalydeco is a cystic fibrosis drug that was approved in the United States in 2012 to treat the 4% of cystic fibrosis patients who harbor a specific mutation in the CFTR gene. Similarly, a number of cancer therapies are designed to target cancers that have acquired specific genetic mutations.
Your genetic make-up can also influence how quickly you break down or metabolize certain drugs, which may make the same dosage of a medication work for one person, but ineffective or toxic for another. Warfarin, commonly known as Coumadin, is an anticoagulant used to prevent blood clots and is an example of a widely prescribed and successful drug for which the dosage can be adjusted based on genetic markers that influence a person’s metabolism. The medical community is not uniformly aligned on the benefits of genetic testing for warfarin dosing, and research is continuing to examine whether genetic testing is helpful in finding the most safe and effective dose for patients and reducing the frequency of adverse reactions and hospitalizations. The field is still developing, and a targeted drug therapy approach informed by genetic testing will not yet work for every patient.
If you are looking to teach these concepts to students or seeking more depth, please see pgEd’s lesson plan on personalized medicine.
- “Questions persist about who pays for genetic testing,” June 2014, pgEd Blog.
- “Gene test helps patients avoid thyroid surgery,” by Susan Young, February 2014, Technology Review.
- “Personalized Medicine may be Good for Patients but Bad for Drug Companies Bottom Line,” by Henry I. Miller, September 2013, Forbes.
- “Smarter medication could save $213B in health care costs,” June 2013, The Associated Press.
- “Research aims to improve personalized cancer care,” September 2012, pgEd Blog.
- “In Treatment for Leukemia, Glimpses of the Future,” by Gina Kolata, July 2012, New York Times.
Genetic discrimination is the unfair treatment of individuals or groups of people based on real or perceived genetic conditions, genetic pre-dispositions, genetic risk factors related to health and disease traits, or ancestry. pgEd has developed an extensive array of materials, many of which are included below, to provide information to those looking to understand the issues, to those wanting to teach about them, as well as resources for if you believe you have a claim of genetic discrimination.
Are there any laws to prevent genetic discrimination?
In 2008, the Genetic Information Nondiscrimination Act (GINA) was enacted in the United States to protect people from genetic discrimination by employers and health insurance companies. The law – often called GINA – has two main provisions. First, it forbids employers to use genetic information to make decisions about hiring, firing and promotion. Second, GINA forbids group and individual health insurers from using genetic information to adjust premiums, add or drop people from policies or deny coverage. GINA protects a person’s genetic information revealed when seeking genetic testing or participating in a research study. It also protects a person’s family medical history, including a family member’s genetic information. For example, an employer can not legally ask an employee if Huntington’s Disease runs in his or her family. This law provides a path of legal recourse for people who believe they have experienced genetic discrimination. The law is enforced by the U.S. Equal Employment Opportunity Commission. GINA has a number of limitations, however. It does not cover people serving in the military (they are covered elsewhere) or extend protections to those seeking life or long-term disability insurance (click here to see a recent article on this by Melissa Healy in the LA Times).
Many hope the passage of GINA will advance medical research in addition to protecting people’s civil rights. GINA also recognizes that a key to genetic research is for people to be willing to participate and feel confident in sharing their DNA with scientists. Only a few cases of genetic discrimination received prominent media attention in the years leading up to the passage of GINA, many of which woven throughout highlighted in pgEd’s curriculum. “Genetics, jobs and your rights” contains many specific examples of court cases and lawsuits over the years that are related to genetic discrimination, and asks readers to consider multiple perspectives on these matters.
An early example of employers and employees struggling with the use of genetic information in the workplace is the Burlington Northern Railroad case. Gary Avary is a railroad worker, he hammered railroad ties for many years. Avary was having arm and hand pain that he thought was carpal tunnel syndrome caused byyears of repetitive tasks on the job. Avary filed a workers’ compensation claim, and the company sent him to a doctor for an exam. He later learned he was genetically tested without his knowledge. The test itself was controversial as the role of genetics in carpal tunnel syndrome is unclear; although the test was intended to look for a genetic predisposition to carpal tunnel syndrome, it actually looked at a genetic marker linked to a rare medical condition, one symptom of which resembles carpal tunnel syndrome. The employer was accused of trying to use the genetic test to prove that the worker had a pre-existing condition as a reason to deny the workers’ compensation claim. The case was settled in favor of Gary Avary. GINA seeks to ensure that workers are comfortable coming forward with workers’ compensation claims knowing their genetic privacy is protected.
Narcolepsy is a sleep disorder that causes excessive sleepiness and frequent daytime naps, called sleep attacks. It may have a genetic component in addition to environmental factors; it may be an autoimmune disease. It is a condition that is varied and complex, with some people responding well to medication while others do not. In this case, Kenya Madden, police dispatcher, disclosed a medical condition, narcolepsy, for which she was being treated and, as a result, was fired. The case was settled with a payment to the employee. It is important to note that in this case, the employee had been living with narcolepsy, and the genetic factors related to her specific case are not mentioned in the story. As such, this case is more likely to fall under other federal anti-discrimination laws, rather than GINA. Employers and employees looking for even more information about GINA might appreciate the FAQ from Genetic Alliance.
Join Rep. Louise Slaughter and show you know about GINA!
In 2014, a small percentage of the US population is aware of GINA and its protections. About 20% of Americans are aware of the law, and only 55% of doctors! Check out the video from Representative Louise Slaughter, one of the authors of GINA and then be counted. Take a short quiz on GINA and pin yourself on our world map!
What is eugenics?
Eugenics is the philosophy and social movement that argues it is possible to improve the human race and society by encouraging reproduction by people or populations with “desirable” traits (termed “positive” eugenics) and discouraging reproduction by people with “undesirable” qualities (termed “negative” eugenics). The eugenics movement began in the United States in the early part of the 20th century; the United States was the first country to have a systematic program for performing sterilizations on individuals without their knowledge or against their will. It was supported and encouraged by a wide swath of people, including politicians, scientists, social reformers, prominent business leaders and other influential individuals who shared a goal of reducing the “burden” on society. The majority of people targeted for sterilization were deemed of inferior intelligence, particularly poor people and eventually people of color.
In the early 20th century, many scientists were skeptical of the scientific underpinnings of eugenics. Eugenicists argued that parents from “good stock” produced healthier and intellectually superior children. They believed that “traits” such as poverty, shiftlessness, criminality and poor work ethic were inherited and that people of Nordic ancestry were inherently superior to other peoples, despite an obvious lack of evidence and scientific proof. However, eugenicists were able to persuade the Carnegie Institution and prestigious universities to support their work, thus legitimizing it and creating the perception that their philosophy was, in fact, science.
The eugenics movement became widely seen as a legitimate way to improve society and was supported by such people as Winston Churchill, Margaret Sanger, Theodore Roosevelt and John Harvey Kellogg. Eugenics became an academic discipline at many prominent colleges, including Harvard University, Dartmouth College, University of Washington and Massachusetts Institute of Technology (MIT), among many others. From the outset, the movement also had critics, including lawyer and civil rights advocate Clarence Darrow as well as scientists who refuted the idea that “purity” leads to fewer negative gene mutations. Nevertheless, between 1927 and the 1970s, there were more than 60,000 compulsory sterilizations performed in 33 states in the United States; California led the nation with over 20,000. Experts think many more sterilizations were likely performed, but not officially recorded.
Adolf Hitler based some of his early ideas about eugenics on the programs practiced in the United States. He was its most infamous practitioner; the Nazis killed tens of thousands of disabled people and sterilized hundreds of thousands deemed inferior and medically unfit. After World War II and the Holocaust, the American eugenics movement was widely condemned. However, sterilization programs continued in many states until the mid-1970s.
How can we as a society avoid the mistakes of the past to take advantage of the promise of genetics?
Today, safeguards have been established to ensure that the ethical implications of new technologies are discussed and debated before being employed on a large scale. In this way, the benefits and advances arising from scientific research and medical procedures can be achieved both ethically and humanely. Examples of the efforts of the United States government to ensure that progress in science, research and technology proceeds in an ethical and socially acceptable manner include the Presidential Commission for the Study of Bioethical Issues, well known for the development of the Belmont Report, and the Ethical, Legal and Social Issues (ELSI) program housed in the National Human Genome Research Institute of the National Institutes of Health (NIH).
Many people fear that new advances in genetics could lead to a new era of eugenics. However, these advances lead to sometimes difficult ethical questions, particularly related to reproductive technologies and embryo screening. As science advances, what traits might people be able to choose or select against? Is it acceptable for prospective parents to have a say in which embryos are implanted in a women’s uterus for non-medical reasons? Is it acceptable for society to dictate this decision to prospective parents? Many of the breakthroughs have saved lives and will continue to do so on a grander scale, and we, as a society, need to discuss the complex issues related to genetic technologies. Debate and discussion can be illuminating even though complete consensus about the intersection of genetics and society will be difficult.
If you are looking to teach these concepts to students or seeking more depth, please see pgEd’s lesson plan and slideshow on history, eugenics and genetics.
 Black, Edwin, War Against the Weak: Eugenics and America’s Campaign to Create a Master Race (Dialog Press, 2003).
 Stern, Alexandra Minna, Eugenic Nation: Faults and Frontiers of Better Breeding in Modern America (Berkeley, University of California Press, 2005).
- Image Archive on the American Eugenics Movement, Dolan DNA Learning Center, Cold Spring Harbor Laboratory. For a critique of eugenics research, refer to the essay by historian Garland E. Allen.
- Timeline of the American Eugenics Movement, Facing History and Ourselves.
- Eugenics in the United States, Wikipedia.
- Presidential Commission for the Study of Bioethical Issues. Topics that have been examined by the Commission include research involving radiation, cloning and the use of embryos. Members of the Commission are appointed by the President and change regularly. Current projects include studying privacy issues in whole-genome sequencing and synthetic biology.
- Ethical, Legal and Social Issues (ELSI) program, National Human Genome Research Institute, National Institutes of Health (NIH). The ELSI program supports research and public engagement in the area of ethics and produces publications that inform the general public about ethical issues.
- “A Summary of Important Documents in the Field of Research Ethics,” Schizophrenia Bulletin (2006) 32 (1): 69-80.doi: 10.1093/ schbul/sbj005. This open-access paper provides an overview of documents including the Belmont Report and the Nuremberg Code. The Belmont Report states that “the primary principles underlying ethical research with human beings are respect for persons, beneficence, and justice. The methods used to recognize these principles are informed consent, risk/benefit analysis, and appropriate selection of patients.”
- “Reparations in North Carolina for victims of forced sterilization,” June 2014, pgEd Blog.