Digital twins of human organs are here. They’re already changing medical treatment.

Twinning

It’s all very well to generate virtual body parts, but the human body functions as a whole. That’s why the grand plan for digital twins involves replicas of entire people. “Long term, the whole body would be fantastic,” says El-Bouri.

It may not be all that far off, either. Various research teams are already building models of the heart, brain, lungs, kidneys, liver, musculoskeletal system, blood vessels, immune system, eye, ear, and more. “If we were to take every research group that works on digital twins across the world at the moment, I think you could put [a body] together,” says El-Bouri. “I think there’s even someone working on the tongue,” he adds. 

The challenge is bringing together all the various researchers, with the different approaches and different code involved in creating and using their models, says El-Bouri. “Everything exists,” he says. “It’s just putting it together that’s going to be the issue.”

In theory, such whole-body twins could revolutionize health care. Trayanova envisions a future in which a digital twin is just another part of a person’s medical record—one that a doctor can use to decide on a course of treatment. 

“Technically, if someone tried really hard, they might be able to piece back who someone is through scans and twins of organs.”

Wahbi El-Bouri

But El-Bouri says he receives mixed reactions to the idea. Some people think it’s “really exciting and really cool,” he says. But he’s also met people who are strongly opposed to the idea of having a virtual copy of themselves exist on a computer somewhere: “They don’t want any part of that.” Researchers need to make more of an effort to engage with the public to find out how people feel about the technology, he says.

There are also concerns over patient autonomy. If a doctor has access to a patient’s digital twin and can use it to guide decisions about medical care, where does the patient’s own input come into the equation? Some of those working to create digital twins point out that the models could reveal whether patients have taken their daily meds or what they’ve eaten that week. Will clinicians eventually come to see digital twins as a more reliable source of information than people’s self-reporting?

Doctors should not be allowed to bypass patients and just “ask the machine,” says Matthias Braun, a social ethicist at the University of Bonn in Germany. “There would be no informed consent, which would infringe on autonomy and maybe cause harm,” he says. After all, we are not machines with broken parts. Two individuals with the same diagnosis can have very different experiences and lead very different lives.