Anthropologist Carla Handley is sitting cross-legged in a mud-walled house in a Kenyan village called Merti. She's meeting with a man dressed in a flowing blue robe and a woven cap of red and white. His name is Wario Bala and he's a member of Kenya's Borana ethnic group, a nomadic people who raise cattle across Kenya's northern regions.

Handley introduces herself, then adds that she's "known locally as Chaltu Jillo Hanti" – the Borana language name bestowed on her by elders in the community. An interpreter translates and Wala laughs approvingly.

Then Handley points to a poster she's brought with pictures on it.

"You see here we have this small brush?" she says. Bala – who never went to school and doesn't know how to read – peers closely at the picture and nods.

"So do you remember in 2017," continues Handley, "when I was here, I was using a brush to rub the inside of people's cheeks? This was the brush I used."

Handley, a research associate with Arizona State University, is doing this presentation to fulfill a promise she made seven years ago, when she teamed up with some geneticists at her university for a study requiring the collection of DNA samples from nearly 600 people.

Back then, says Handley, the elders in the community had made a request that's almost never demanded of researchers: "They said, 'We will only allow this if you promise to return and tell us what it is that you found.' "

Handley readily agreed. But getting the money to do so proved even more complicated than she first imagined. It's only in the last several months – through a new project funded by a branch of the United States National Institutes of Health that focuses on ethics in research – that Handley has been able to make good on her commitment.

The project isn't just about providing Handley's study subjects with the results of her work. Handley and a collaborator are using that effort as a test case to launch a broader re-think of what Handley calls "some deep ethical questions that should be asked." Essentially, what do researchers owe their human subjects when they collect DNA for studies – and all the more so when the participants are from some of the world's most marginalized communities?

To find out, Handley surveyed members of the Borana and three other nomadic peoples in northern Kenya and is now analyzing their views on a host of issues: Should researchers compensate people who provide their DNA samples – and if so, what form should that compensation take? If future researchers want to use stored samples for a new inquiry, do they need to go back to the people who donated their DNA to get their consent? And to what extent do people think they ought to be kept informed about the results?

When it comes to explaining findings, Handley has also come up with a new, picture-based method. She's assessing the its effectiveness in hopes of providing a model for how researchers can meaningfully involve study participants who've never had the opportunity to learn to read – let alone get a grounding in biological concepts such as DNA.

Arthur Caplan, a professor of bioethics at New York University, says Handley's effort is "pathbreaking."

It's a moral principle, says Caplan, that "subjects have the right to know the results of research. "If we think of study subjects not so much as objects, but as partners that we're going to work with, then I think we really have to make a sustained effort."

Yet, says Caplan, historically "there's been a lack of appreciation for the duty to return findings to subjects around the world – rich and poor alike."

For instance, he notes, a 2019 study found that among clinical trials between 2014 and 2015, only about 25% had provided participants with summaries of the findings using language meant to be understandable to someone who is not a scientist.

This has started to change over the last several years, adds Caplan, as a growing number of government officials and scientists in wealthy countries such as the United States and the United Kingdom have started to show interest in finding ways to inform study participants in their countries about the results.

But Caplan, who is leading one of those efforts, says Handley's project is the first he's heard of that is attempting to reach people in communities as remote and impoverished as the nomadic peoples of rural Kenya. So her work could offer useful insights for reaching traditionally ignored and underserved populations everywhere.

"There can be lots of strategies to get it done," he says. "I think this work is showing the way."

The quest that started it all

How did an anthropologist like Handley find herself at the cutting edge of a movement to reconsider the ethics of genetics research?

It began with her quest to answer a longstanding question in evolutionary anthropology and biology: Why do we humans cooperate with each other on such a massive scale — with people well beyond our families, or even extended families? This trait, so different from the behavior of even primates with whom we share recent ancestry, is arguably one of the secrets to our success as a species, notes Handley.

"Because of this level of cooperation within our species, we've been able to fill every niche on earth and exploit it to great effect," she says. "So what has made this happen?"

One possibility is what's called "cultural selection theory." The idea is that as humans developed different cultural arrangements, the cultures that did best – and therefore lasted through time – were those with strong norms requiring people to help out fellow members of the culture, even as they competed against people from outside cultures.

Handley and a collaborator had already provided important evidence for that theory through an anthropological study they published in the journal Nature. It found that the Borana — and three other neighboring nomadic peoples — were very willing to share precious resources like water and grazing land with strangers within their own ethnic group. But when it came to members of the other groups, says Handley, "The level of cooperation really drops off, because you've identified them as culturally distinct from you, and so you want to make sure that that border is maintained."

But Handley and her collaborator had still wanted to rule out another possibility: Maybe people were favoring members of their own culture because they're simply more likely to be biologically related to them — in other words maybe this just boils down to people's evolutionary instinct to pass on their genes.

Hence the effort to collect those cheek swabs and compare the DNA in the samples from each group. Handley's finding: the genetic explanation does not hold.

These four nomadic groups may have different languages, religions and styles of dress, "but there is a high level of genetic relatedness between them," she says. What's more, the best predictor of how genetically related two individuals are to each other is not which ethnic group they belong to but how close they live to each other.

"Everybody should have that right."

The team published their results in the American Journal of Biological Anthropology in April of 2022. But sharing the findings with the study participants required Handley to get more creative.

Tracking down the study subjects was going to be time-consuming and expensive. And when it comes to the typical research grant, she says, "there is nothing that allows for money to be kept aside for the purposes of dissemination. That goes for genetics projects, that goes for anthropology projects – for all kinds of research that is conducted within human populations."

Still, Handley, who has built her career on studying the nomadic peoples of northern Kenya, felt a kind of sacred responsibility to keep her word. "These are communities and people that I've had relationships with for so many years," she says.

She also found herself quickly coming around to the idea that reporting back to study subjects is important on principle.

"Being self-determined, having autonomy over your own data, how it's consumed, how it's presented, how the rest of the world views your community – I mean, everybody should have that right," she says.

But all the more so, she adds, when it comes to people in remote, low-income regions.

The rest of us, she notes, "have every kind of platform available to us. You can go on social media – you can complain or raise different perspectives. But people in these kinds of communities in northern Kenya don't have that access. People are not literate. If you publish a paper in Science or Nature they're not going to read how we as Western researchers are representing their communities and their genetic information."

Caplan, the bioethicist at New York University, says a similar sentiment is also starting to drive a change in wealthy countries.

"A lot of clinical trials just recruit upper class white people – or they may only recruit people in countries that are relatively wealthy, ignoring for medical or social science purposes vast populations," he says. So "there's been a lot of discussion about, 'How do we get a more representative group of people?' Well, one way to do that is to make the subjects feel that they're partnering with you – that they're working with you. Not that you're the researcher, the big Kahuna, and they're just out there as some kind of fish to be looked at swimming in the ocean."

Caplan notes that the British government has announced plans to require medical researchers to either provide their study results to participants "in a suitable format," or explicitly explain why that's not feasible. And, adds Caplan, he's "not surprised," that it was the U.S. National Institutes of Health that finally provided Handley with the funding she needed for her project.

The Explanatory Power of Beads

Once Handley finally got that support, she confronted the next challenge – coming up with a way to actually explain the study's results to people who had never even heard of DNA.

Then it hit her: "One thing that is ubiquitous across these groups is the use of beautiful, elaborate beading that women, and some men as well, wear in necklaces," says Handley. "Different groups have different coloration of their beads – different styles."

And in many ways the beads offer an excellent analogy to DNA. "You can line up different strings of beads and have the varying colors to show the differences in the DNA between groups. And so it's something that I just thought, 'Okay, this is something that everyone can understand.' "

Which brings us back to Handley's meeting with Wario Bala in the mud-walled house. After explaining that inside the cheek samples were tiny things called "cells," which contained something even tinier called "DNA," Handley points to two pictures on the poster: A man in the traditional attire of the Turkana people and a woman dressed as a member of Bala's group, the Borana.

Handley takes out two beaded necklaces and places one on top of each figure. "So these black beads are a representation of the DNA that is common to all of us as human beings. We all share these black beads," she says. "But then we can see some small colored beads – like this red one, this blue, this yellow, and this orange," she says. "This represents the DNA that is a little bit different between us."

Then she compares the two necklaces – bead by bead. "You see this one - first [bead] is orange, on this one the first one is yellow. Different," she says. Next up: "Red. Yellow. Different." But then Handley gets to the third bead in each strand. "Red, Red. Same."

As she continues the analysis for each of the different ethnic groups and sub groups pictured on the poster, Wala leans in ever closer.

"Thank you," he says, when the presentation has concluded. "This is knowledge that we have been passing on through speech. But now you have written it down."

Handley says other participants have expressed more surprise at how much genetic material they share with members of the other ethnic groups. "Just sort of a light bulb moment of, 'Oh my goodness, I had no idea that I was competing or fighting with essentially my brother.' "

In an interview with NPR, another participant, Hussein Dida, says he was surprised to see how much DNA Black Africans shared even with white people.

"I knew that the white and the Black we're all human beings, of course," he says. But I thought there is no way we have anything shared with them. Now I've noticed that we share almost everything – just only small differences between us."

Handley says responses like this upend a widespread assumption that people without formal education who are struggling with poverty wouldn't be all that interested in big picture questions about humankind. "People are curious about the world. They're curious about themselves," says Handley. "And even I – working there for a long time – didn't give people enough credit for the amount of curiosity there was."

Indeed another study participant, a middle-aged woman who asked to remain anonymous because she feared that relatives might disapprove of her choice to provide a cheek swab, says she thinks it's important for researchers to continue using her DNA for further studies.

But they need to keep her informed, she adds. After all, she says, "What I gave is a part of my body."