The Power of DNA: From the Human Genome Project to Precision Medicine

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In celebration of DNA Day this year, we invite you to discover what makes you uniquely you with a MyHeritage DNA test — now on sale for our lowest price of the year, with our special Stay at Home Sale!

Deoxyribonucleic acid…DNA. It’s one of the most important discoveries of all time, and it continues to be the information foundation for many medical advances. There is much to study and understand about the power of DNA. That is the intent behind DNA Day, a day for students, teachers, and the public to learn more about genetics and genomics. This celebration commemorates two critical moments in the history of genetics – 1) The discovery of the double-helix structure of DNA in 1953, and 2) The completion of the Human Genome Project in 2003, a ten-year project to sequence the entire human genome.

The Human Genome Project Timeline contains major milestones in genetic research from 1865 to 2003 [Credit: Human Genome Project Timeline]
The Human Genome Project Timeline contains major milestones in genetic research from 1865 to 2003 [Credit: Human Genome Project Timeline]

Why are those discoveries so important? The first helped us find out how DNA is constructed. DNA is made from two single strands that wind around each other to create a double helix. Understanding that and its ability to unwind for replication and repair led to the research that revealed what it does, how it works, what happens when it changes or mutates, and how it’s message is passed on from generation to generation. The Human Genome Project took that knowledge and made it functional. Sequencing the human genome is what allowed us to move medicine from just treating symptoms to something that can be completely tailored to the individual by analyzing their unique make up of DNA. This shift in how we think about medical care has resulted in an entirely new discipline known as precision medicine.

To fully appreciate the potential of precision medicine, it helps to understand the structure of DNA and how it is unique from person to person. Most humans have 23 pairs of chromosomes that are passed down or inherited from their parents, one of each pair from Mom and one from Dad. On each chromosome are located a certain set of genes. In total, humans have 20,000-25,000 genes across the genome. Each gene is made up of some combination of 4 nitrogen bases – Adenine, Thymine, Cytosine, Guanine. Those bases pair with each other in a specific way (A-T, C-G) to create the double helix ladder structure of DNA; the base pairs form the rungs of the ladder.

In the DNA double helix, the strands are connected by hydrogen bonds between the bases that pair in a specific way (A-T and C-G)[Credit: Anatomy & Physiology, Connexions]
In the DNA double helix, the strands are connected by hydrogen bonds between the bases that pair in a specific way (A-T and C-G)[Credit: Anatomy & Physiology, Connexions]

There are more than 3 million bases in human DNA. The human genome is the “code” made up by those bases. That code is 99% the same across all humans. It is the 1% that makes each individual unique. You may have more of your DNA in common with some groups of people over others. For example, you have more shared DNA with those who have similar ethnic origins as yourself, and even more among your biological family members.In the MyHeritage DNA test, your Ethnicity Estimate is determined by comparing your genetic variants across your genome to models of 42 different ethnicities from around the world. You are then provided a breakdown of which percentages of your DNA match each of the different models — results that are made possible thanks to our Founder Populations Project. For your list of DNA Matches, your DNA is compared against our DNA database to find similar sequences that indicate that a piece of your DNA was likely inherited by two or more people from a common ancestor or ancestors.

In addition to learning more about your ethnic origins and finding unknown relatives, studying, understanding, and most importantly, developing ways to apply the 1% difference to taking control of your health is the basis of precision medicine.

According to the Precision Medicine Initiative, the definition of precision medicine is “an innovative approach to tailoring disease prevention and treatment that takes into account individual differences in people’s genes, environment, and lifestyle.” The first time precision medicine was used to treat patients was in the field of pharmacology. Scientists and healthcare providers recognized that when given the same drug, some individuals respond as expected, some not at all or the medication is less effective than expected, and some have bad side effects. But why?

It turns out that genetic changes, that 1% that varies from person to person, can help predict how the body will respond to certain drugs. The study of this effect is called pharmacogenomics. Use of pharmacogenomics informs healthcare providers as to which drugs may be most effective for their patients. It also assists in avoiding serious side effects which can be a significant cause of hospitalizations and death. Current applications of pharmacogenomics include testing for conditions like malignant hyperthermia, which is one of the Genetic Risk Reports provided in MyHeritage’s DNA Health test. People with this genetic change can be given other forms of anesthesia to prevent serious complications when having surgery.

Precision medicine is also starting to be used to treat cancer. Through advanced DNA sequencing technology, researchers saw that tumors themselves have their own genomic profile. Even people with the same type and grade of cancer may not have the same tumor profile. That genomic profile can, in some cases, predict how or even if the tumor will respond to certain treatments. Historically, the strategy was to give everyone with a certain type of cancer the same course of treatment. With precision medicine, now the strategy is to give everyone with the same genetic variants the treatment that we know works on those variants, regardless of the type of cancer. 

Precision medicine in cancer treatment [Credit: www.cancer.gov]
Precision medicine in cancer treatment [Credit: www.cancer.gov]

Our growing understanding of genetics made possible by the work of the Human Genome Project has created an opportunity to apply precision medicine to many aspects of clinical care and public health, including the recent COVID-19 global pandemic. We are just beginning to understand how the virus works, and who is most at-risk to become infected. We know that the elderly and those that are immunocompromised are at higher risk to have worse symptoms of the virus. This is likely because their body is less able to fight the infection. However, it is also possible people with a certain genomic profile may be more likely to get COVID-19. Similarly, treatment options for the coronavirus may have different effects on people with different genomic profiles. Also, some treatments may cause adverse effects in certain people depending on their genomic profile. Part of the research needed on this virus is learning more about how precision medicine may play a role in developing effective and safe vaccines, prevention techniques, and treatments.

Precision medicine is currently focused on using genomic data to treat or prevent a disease. The future may involve applying the principles of precision medicine to a much broader scope of factors. The concept of Precision Health involves measuring and acting on all of the factors that impact your health including genetics, behavior, and your environment. Precision health would, therefore, be relevant to all individuals – both those currently dealing with a health condition and those that are healthy now and want to stay that way. This is a significant goal of the MyHeritage DNA Health test, making genomic-driven health information accessible and affordable so it can be used to help you more effectively manage your health.   

The power of DNA, and the information held therein, is just starting to be fully realized. The widespread use of precision medicine is still relatively new, but its potential to make healthcare delivery more accurate, effective, and safe is unparalleled. It also has tremendous potential in helping all of us take control of our own health by using the information bound up in our DNA to take proactive steps to adjust our behavior and lifestyle, maximizing our ability to live healthier lives. We think that’s worthy of a celebration.

Happy DNA Day!

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