How Genetic DNA Ancestry Testing Improves Disease Diagnosis and Personalized Treatment

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• Moving Beyond Race: The Importance of Individual Genetic Ancestry
• A Personal Genome Example: Global and Local DNA Ancestry
• How Genetic Diversity Impacts Disease Risk and Drug Response
• Asthma Research Breakthrough: A Eureka Moment in Genetics
• Hispanic Health Disparities and the Role of Ancestral DNA
• The Future of Precision Medicine and Public Health Impact
• How Life Experiences Shape a Career in Genetic Research
• Full Transcript

Moving Beyond Race: The Importance of Individual Genetic Ancestry

Dr. Esteban Burchard, MD, emphasizes that the traditional concept of race, often based on self-reported skin color or facial features, is outdated for medical purposes. What truly matters for health is an individual's specific genetic ancestral DNA makeup at the level of each gene. This precise understanding of DNA ancestry is critical because it directly determines a person's susceptibility to various diseases, including asthma, multiple sclerosis, and different cancer types.

This shift in focus from broad racial groups to individual genetic mapping is a cornerstone of modern precision medicine, enabling more accurate diagnoses and personalized treatment plans.

A Personal Genome Example: Global and Local DNA Ancestry

To illustrate real genetic diversity, Dr. Esteban Burchard, MD, sequenced his own genome using a service like 23andMe, analyzing a million genetic markers. His global DNA ancestry breakdown revealed he is 25% Native American, 7% African, and of European descent. However, the more critical medical information came from analyzing his local DNA ancestry, which shows the origin of specific genes.

Dr. Esteban Burchard, MD, explains, "My insulin gene is Native American in origin. This puts me at high risk for diabetes." This example demonstrates that disease risk is not uniform across an entire person's ancestry but is instead linked to the origin of specific, critical genes.

How Genetic Diversity Impacts Disease Risk and Drug Response

The implications of this genetic DNA ancestry diversity are profound for personalized medicine. Populations often considered homogeneous, like Europeans, actually contain significant genetic gradations. Dr. Burchard points to Russia as an example of a tremendously diverse country with many different ethnic groups whose mixing throughout history has created unique genetic summations in individuals today.

This genetic variability means that responses to medications, known as pharmacogenomics, and predispositions to diseases like cancer can vary significantly even within groups that appear similar. Incorporating genetic ancestry testing into a medical second opinion ensures this vital information is considered for a complete cancer diagnosis and the best personalized treatment strategy.

Asthma Research Breakthrough: A Eureka Moment in Genetics

Dr. Burchard's research provided a pivotal eureka moment when his team led a clinical trial comparing asthma severity in African Americans and Caucasians. They discovered that African Americans die more often from asthma and identified a specific gene associated with severe lung disease that was 40% more common in African Americans.

Dr. Esteban Burchard, MD, states, "The light bulb was switched on. All the differences that we see between populations might in part be explained by genetic differences." This discovery set the course for his life's work, proving that genetic ancestry is a key factor in health disparities.

Hispanic Health Disparities and the Role of Ancestral DNA

Dr. Burchard next turned his focus to Hispanic populations, where he found stark health disparities. Hispanics on the U.S. East Coast, who are primarily of Puerto Rican origin, had a three-fold higher prevalence and death rate from asthma compared to other Hispanic groups. Understanding that "Hispanic" is not a genetically uniform category, Dr. Burchard and his team hypothesized that ancestral DNA differences were the cause.

Since 1997, they have built the largest minority children's dataset in the United States, which has been funded by the National Institutes of Health to study whole genome sequences and drug response across different racial and ethnic groups.

The Future of Precision Medicine and Public Health Impact

The work of Dr. Esteban Burchard, MD, demonstrates that the results of genetic ancestry research have a significant clinical and public health impact that extends far beyond minority groups in the United States. The principles of genetic diversity apply to all global populations, including the diverse ethnic groups across former Soviet republics and worldwide.

By moving beyond outdated racial categories, precision medicine can leverage genetic DNA testing to improve health outcomes for everyone, making findings from studies on specific groups universally relevant to improving cancer diagnosis and treatment everywhere.

How Life Experiences Shape a Career in Genetic Research

Dr. Burchard's unique personal journey fundamentally shaped his scientific worldview and career path. Growing up in a multi-ethnic San Francisco household with a Hispanic mother and a period living with a Chinese family, he was exposed to diverse cultures and languages from a young age. He attributes his discipline and stamina to his time as a wrestler, coached by an African-American Olympian.

Dr. Anton Titov, MD, noted that these ethnically diverse experiences—from a Hispanic and Chinese upbringing to Jewish housemates and black coaches—directly influenced Dr. Burchard's path in medicine. Dr. Burchard concludes that this background allowed him to fuse a "personal passion with academic rigor," driving his mission to understand how genetics and environment interplay to affect health.

Full Transcript

Genetic DNA testing for racial DNA ancestry is popular, but genetic mapping of ethnic origin can help find cancer risk factors. Ancestry DNA tests can help autoimmune disease diagnosis and treatment.

Genetic DNA testing for racial DNA ancestry and ethnic origin is important at the individual genetic level. It determines susceptibility to disease, including asthma and multiple sclerosis.

Dr. Anton Titov, MD: Today, ethnic origin is often based on self-reported skin color or facial features. Your research shows this.

Dr. Esteban Burchard, MD: The notion of race as a large homogeneous group is outdated. What matters is genetic ancestral DNA makeup at the individual gene level.

Dr. Anton Titov, MD: We just discussed this in several questions. Each person has many often unexpected ancestral DNA origins of genes. You sequenced your own genome, so perhaps on your own example you could illustrate the real genetic diversity of each individual. Please discuss the implications of genetic DNA ancestry diversity for modern personalized medicine.

Dr. Esteban Burchard, MD: I used a company called 23andMe. Each of us has 23 chromosomes from our mom and our dad. We used a million genetic markers and precisely estimated what my global DNA ancestry was. Then we estimated my local DNA ancestry.

My global DNA ancestry is 25% Native American, 7% African, and I am also European. But I could tell you this about my local DNA ancestry: my insulin gene is Native American in origin. This puts me at high risk for diabetes, which is the case for many populations in Europe.

Europeans tend to be more genetically homogeneous than Hispanics, but that doesn't mean Europeans are all the same. It means that there is a gradation. We know that Russia is a tremendously diverse country. You have different ethnic groups from east-west and north-south.

You have great historical events that happened in Russia that led to the mixing of different cultures. Today we're a summation of all those different events.

Dr. Anton Titov, MD: It's very interesting, some of the stories that you previously discussed. The way you were brought up in San Francisco, how you grew up in a truly multi-ethnic and multicultural background, really influenced your personal path in medicine. This determined the choices you made in life. That's how the genes and environment interplay at each level.

Dr. Esteban Burchard, MD: Yes, it was fascinating. My mom was a migrant farmworker. She was Hispanic, very dark, and did not speak English. She learned English, went to school, and became a schoolteacher. My dad was Caucasian, but they got divorced. Finances got very tight, and we were helped by a Chinese family who took me in. That made it a fun childhood experience.

I went to Chinese school for two years and spent a lot of time in San Francisco Chinatown, which is world-famous. I got into high school and needed discipline, so I started wrestling. It's one of the great sports and the oldest sport in the world.

My coach was an African-American on the 1984 US Olympic team who won the Tbilisi tournament in wrestling. There are a lot of people who are quite famous wrestlers from the Soviet Union republics, like Uzbekistan, Iran, and so forth. My clinical trial partner was also an African-American NCAA finalist. He was the best you could be in college.

I took that wrestling discipline and applied to medical school. Once I did that, medical school was relatively easy. Yes, it was hard, and it was one of the biggest accomplishments I have ever had. But going from my college to Stanford really was a testament to the discipline I learned in wrestling.

I graduated top of my class at Stanford and went to train at Harvard's Brigham and Women's Hospital. I went from my college of 30,000 students to a medical school class of 86, then to a residency class of 42, and came back to UCSF with a class of six. At every level, the microscope kept getting harder, more focused, and more focused.

I attribute a lot of my stamina, persistence, goal setting, and visualization to what I learned in wrestling. I'm very grateful to have had those experiences and all the ethnically diverse experiences.

I went from a Hispanic family where I spoke Spanish to a Chinese family where I learned Chinese. I then did medical school and lived in a Jewish house for two years. I had black wrestling coaches throughout for ten years. It has been a tremendous experience that basically shaped my view of science.

I was at Harvard, and it really opened up an opportunity. I call it a personal passion meets academic rigor. We led a clinical trial looking at African Americans and Caucasians for asthma severity. African Americans die more often from asthma.

We identified a gene associated with lung severity disease that was 40% more common in African Americans. There was a Eureka moment for my career; the light bulb was switched on. All the differences that we see between populations might in part be explained by genetic differences.

That just set me off for the rest of my life. I started looking at Hispanics. Hispanics on the East Coast had a threefold higher prevalence rate of asthma and a threefold higher death rate from asthma compared to other Hispanics. Hispanics on the East Coast are primarily Puerto Rican.

Being Hispanic myself, I just put one and one together. There were ancestral DNA differences between the groups. We have done that and have been working on this since 1997. It's been tremendous.

We are the only ones in the country that have this resource. We built the largest minority dataset in the United States for children. We just got funded by the National Institutes of Health to look at whole genome sequences in drug response between different racial groups.

We are making not just scientific impact but a clinically significant impact and a public health impact. But the results are not just relevant to Hispanics or African Americans in the United States; they are relevant to all populations.

That's why I go back to all the different countries in the former Soviet Union, Uzbekistan, Kazakhstan. They're all great wrestlers. You are not a homogeneous population as well.

Dr. Anton Titov, MD: So that's a very important implication. DNA testing for racial DNA ancestry and ethnic origin: broad racial groups are outdated. Genetic DNA ancestry at the individual gene level is important for diseases.