Is race a cloudy lens to view genetics?
Often we think research and medicine are above the fray, but in an election year, hot-button issues touch everything.
Public health researcher Michael Yudell and his colleagues argue that doctors and geneticists should stop relying on broad, sweeping race categories.
Yudell is chair of the department of community health and prevention in the Dornsife School of Public Health at Drexel University.
Culturally, politically, legally, historically, race has deep meaning for many people. When we fill out a census form, we check Asian, white, black, Pacific Islander—and—or American Indian. Those divisions aren’t in our genes, Yudell said, but they are deep in our social DNA.
There’s no biological basis for the common ways we define race, he said.
“It’s not as if all so-called white people have one set of genes, and so called black have another, and all Asians have another set of genes,” Yudell said.
Genetic research is important, he said, medicine needs to understand how people are different at the genetic level.
“We are better off looking at individual genes and we’re better off looking at subpopulations within big racial groups. It still won’t get us the 100 percent answer that we want but it will be better than the big continental racial groups that we, for too long, depended on,” Yudell said.
He just doesn’t think that there’s a gene trait—a predictor of illness—that is universally shared by all self-described Asians, for example.
“Even if 90 percent of the population carries that one trait, that means 1 out of 10 people–in a population that adds up pretty quickly—are not going to be served by that racial prediction,” he said.
Yudell says race is a cloudy lens to see health difference.
“Race has been used to oppress people, race has been used to kill people. Does science really want to be using a concept that is so historically loaded?” Yudell said, adding that it can also be bad medicine.
Partly it’s about assumptions. Let’s say you take your sandy-haired, green-eyed three year old to the doctor with swollen hands and feet–and really bad joint pain. Those are classic signs for sickle cell anemia. But in this country sickle cell is often wrongly thought of as a black disease. If the physician looks at your kid and decides she’s white, the physician may discount sickle cell as a possibility—and that can delay diagnosis and care.
In the United States, sickle cell disease is most common among people with ancestors from West and Central Africa. But the trait is not related to skin color. The gene variant evolved in regions of the world with lots of malaria—including the Mediterranean, South Asia and parts of the Middle East. Anyone with that heritage could have the trait running in the family, that includes a Caucasian kid, whose great grandparents happen to be from Spain or Greece.
Many scientists who concede that race is a crude, blunt instrument in medicine argue that right now, race and race-based medicine are some of the better tools we have to eliminate health disparities.
African gene variant?
Maureen Murphy is trying to better understand why cancer hits different populations of people differently.
Murphy says she’s been thinking about curing cancer since she was a 12 year old in Catholic school. Today she runs a laboratory at The Wistar Institute, where she leads a team of young postdocs and junior scientists.
There’s something about Murphy—maybe it’s the puffy vest or the no-nonsense haircut–that makes you think she loves hiking, maybe. You can just tell she’s outdoorsy. And yet, for nearly two decades, Murphy built a career under fluorescent lights, in biology labs.
“My dream is to be able to tell people, this is a drug that will melt your cancer away,” she said.
About five years ago, she began to focus on disparities. For example, in the United States, Caucasian women are more likely to get breast cancer, but African-American women are more likely to die from the disease.
“And to date, no one knows why, and I thought to myself, I think I might have the reason why,” Murphy said.
Her guess? An African gene variant, or S47.
S47 is a hiccup in DNA–way down below the cell level.
The mutation sits on an anti-cancer gene that scientists call a “superhero” tumor suppressor. That gene’s only job is to detect cancer—and shut it down. But in some people, S47 somehow gums-up the works and, suddenly, the superhero gene does a bad job of fighting cancer. S47 has been found most often in black people.
“In about one out of 50 African Americans, and about one out of 60 Hispanic-Americans. It’s more common in Africa. It’s about one in 10 in Africans. Caucasian Americans, 0 out of 8,800,” Murphy said.
While Murphy casually refers to S47 as the “African gene variant,” she says it’s clear it’s not a universal trait of people born on the continent, or their descendants.
“We genotyped—we looked for S47–in 20 different groups of individuals all around Africa and we only found it in sub-Saharan west Africa,” she said.
Still S47 might be a great divining tool someday. A starting place for tailoring healthcare, Murphy said.
“So what I’d like to do now, is to look at families of African Americans where cancer seems to be stalking that family, because I would like to ask the question, is S47 the reason why?” Murphy said.
Murphy thinks the answer is going to be “yes.” But she hasn’t tested enough people yet to know for sure—to convince her peers–or to get her hypothesis published.
But for Murphy it’s a heady time. Her team is looking for the best drugs to kill S47 cancer tumors.
“I view science as a roller coaster, you know there’s the first part where you’re cranky and clunky, and you don’t know what’s happening, right now, for me, S47 is I have direction, I’m going up the hill, right? Then I’m going to find that drug that will kill those tumors tenfold better and I’ll go down the hill and have the thrill,” Murphy said.
She says science could be few inches closer to figuring out why black people are harder hit by some cancers.
“I think it’s absolutely true that there are genetic determinants of cancer that are ethnically biased, there’s no question,” she said.
Murphy is great at explaining the complicated molecular genetics, but I stumped her with a basic question: What is race?
“I don’t know, what is race? I don’t know the answer to that,” she said. “It’s history.”
Even for scientists who deal in precision and accuracy, it’s tough to talk about race.
“I guess, you know, the problem is we tread into political correctness, here, to some extent,” said cancer researcher Jim Manfredi, who runs a basic science laboratory at Mount Sinai Health System in New York.
He says a good doctor wants to know about a patient’s family history of health and disease, and sometimes asking about race is a quick way to get to those answers.
“Without explaining, if somebody said: ‘Is your mom white or black?’ They’d be like ‘WTF, you know, what are you after here? None of your business.’ I think the question has to be framed properly.
Manfredi isn’t ready to scrap race from science.
“Especially in the case of disease, we shouldn’t shy away from discussing this because it’s so important to sort this out,” Manfredi said.
“My family background is more Mediterranean, and so I tan, I don’t burn. Somebody from British extraction, burns rather than tans in the sun. Their incidence of skin cancer is going to be higher than my incidence of skin cancer, that’s all variance in the population that’s genetically based and you can’t ignore that, it just can’t be ignored.”
That’s part of the argument for keeping race and ethnicity in science and medicine.
If researchers ever do move away from using broad race categories, it’s not clear yet what would replace those classifications. Race historian Michael Yudell and his colleagues suggest that a national panel of science experts should hash it out.
They say it might make sense to ask about ancestry. Is a patient’s family from West Africa versus East Africa, for example.
Whether it’s shared ancestry or shared genes, cancer researcher Maureen Murphy doesn’t seem too hung up on what you call the people she’s trying to help.
“We see lots of pedigrees—pedigrees are all the family members—of African American families, where there are multiple people in their 40s and 50s getting cancer, all sorts of cancer, a lot of breast cancer, a lot of colorectal cancer,” Murphy said.
“Those are the families that we are trying to target,” she said. “And ask the question, are they getting it because they have S47?”
Murphy said she wants to be able to look at someone’s genes, know what’s gone wrong to cause cancer and use that information to recommend the best treatment.