Physician-scientist navigates own health challenges to reach heights of 25-year career

Eric Sibley was diagnosed with multiple sclerosis just as his career in pediatric gastroenterology was taking off. But in his unique circumstances, he unlocked his potential as an academic advisor and role model.

- By Julie Greicius

Eric Sibley, professor of pediatric gastroenterology, arrived at Stanford in 1993 to work in the lab of Gary Gray as a postdoctoral scholar.
Steve Fisch

At first, the symptoms were so subtle he hardly noticed them.

Sometimes his foot would catch on the ground when he walked. “I would stumble a little bit,” said Eric Sibley, MD, PhD, professor of pediatric gastroenterology at the School of Medicine. “Gradually it became more pronounced, until it was an obvious limp.”

A young physician-scientist, Sibley’s focus was on the patients he cared for and the scientific discoveries he was working to achieve. Since his arrival at Stanford in 1993 as a postdoctoral scholar, he’d been investigating why the gene involved in making lactase, an enzyme responsible for lactose digestion, gets turned off in most mammals after they’re weaned. His goal was to understand the gene regulation behind this developmental phenomenon and apply what could be learned to regulating other genes in the gastrointestinal tract.

He cared for patients in the pediatric gastroenterology clinic at Lucile Packard Children’s Hospital Stanford. “The dominant theme of Eric’s practice is caring about the people who need it most,” said Dorsey Bass, MD, associate professor of pediatric gastroenterology, who shared a Friday afternoon clinic with Sibley for two decades. Some of Sibley’s patients, Bass said, were “very financially distressed and with multiple disabilities, kids with cerebral palsy and lots of complicated, difficult issues. Eric’s loyalty to them and their loyalty to him just always, well — it makes you a little proud to be a human.”

Sibley couldn’t yet know how his own medical diagnosis would affect his life and career path. While his physical limitations would not change his aspirations, they increasingly opened him to his strengths as an academic mentor and role model of resilience.

A persistent shoulder injury

When he wasn’t working, Sibley enjoyed time with his wife, Carol Somersille, MD, an obstetrician-gynecologist, and their two children, Carl Somersille Sibley and Lauren Somersille Sibley, whom he credits with providing invaluable support. Sibley coached his son’s and daughter’s basketball teams. He played golf and softball, too. But after a round of golf in 1999, Sibley became aware of a shoulder injury that wouldn’t go away. 

Sibley received the Distinguished Service Award from the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition in 2017.
Craig Huey Photography

An MRI of his shoulder didn’t show much, but looking toward Sibley’s spine, the doctor noticed demyelinating lesions — evidence that the protective covering, called myelin, around his nerve fibers was damaged. It wasn’t enough for a diagnosis of multiple sclerosis — a brain and spinal cord disease in which the immune system attacks the myelin wrapping of nerve cells — but it was suspicious.

Sibley’s official diagnosis didn’t come until many years later, but when it did it was severe: primary progressive multiple sclerosis, the most aggressive form of the disease.

For Sibley, the adjustment to becoming a patient — a doctor-patient using a cane, then forearm crutches and eventually a wheelchair — was challenging. “Until I developed MS, I was thinking, ‘OK, I’m going to be able to do everything,’” he said. “It was a big psychological evolution to be able to accept that, yeah, there are going to be limitations on what I can do and how people are going to perceive me. The first real hurdle was using a crutch at all.”

A career interrupted

Sibley’s career had gained remarkable momentum in the years before his diagnosis. He’d been appointed to the role of assistant professor in 1999, and two years later received his first research project grant from the National Institutes of Health. The grant would support his work characterizing the genetic determinants of intestinal lactase persistence in humans. In 2004, he became a member of an NIH study section in which he participated in reviewing and recommending grants. The following year he was elected to the Council of the Society for Pediatric Research. In 2006, he became editor-in-chief of the Journal of Pediatric Gastroenterology, and that same year was promoted to tenured associate professor at Stanford. He went on to become chair of the growth, development and child health section of the American Gastroenterology Association.  In 2010, his achievements in academic medicine were recognized by induction into the American Clinical and Climatological Association.

“All those things were lining up, and if I had been able to continue at that pace healthwise, I was on a trajectory to continue as a leader in those different societies,” Sibley said. “So that became a bit of a frustration, to have everything lining up perfectly, but then have the realization that I can’t keep traveling to these national leadership meetings. It’s just too hard on the body.”

Lynne Olds, a research associate in the Sibley lab, recalled learning of his diagnosis around 2010. “Eric came to the lab to tell me he’d been diagnosed sometime before but had not made it public,” Olds said. “My private reaction was profound sadness that this was happening to such a good man.” Olds focused on making accommodations in the lab so that Sibley could continue working. “I wanted him to know that this was his lab, and whatever it took to make it possible for him to be physically in it would be done,” she said.

Support from his colleagues helped Sibley focus on moving forward. “As his disability evolved, some of the procedures that he wasn’t able to do I took on for him to some degree,” Bass said. “Maybe the most remarkable thing is: It didn’t really seem to change who Eric was. He addressed his disability, like, OK, how are we going to work around this? How can I keep going?” 

Minority in medicine

Sibley’s illness puts him among the 2 to 10 percent of practicing physicians with a disability, according to a 2005 study in the American Journal of Physical Medicine & Rehabilitation. Yet, as an African-American, Sibley was already well aware of what it meant to work as a minority in medicine. Only 4 percent of full-time medical school faculty identify as black or African-American, according to the Association of American Medical Colleges. Sibley attributes his perseverance in the discipline to his mentors who had paved the way.

Sibley’s father, William Sibley, MD, practiced family medicine in South Los Angeles, not far from the family’s home in the View Park-Baldwin Hills neighborhood. “View Park-Baldwin Hills was one of the few neighborhoods in the west side of Los Angeles where African-American professionals and entertainers could purchase homes with less realty discrimination,” Sibley said. “We lived across the street from the jazz singer Nancy Wilson. And Ray Charles was two blocks over. Ike and Tina Turner were one block over.” Sibley had two younger brothers. His mother, Mary Hall Sibley, managed the household.

Sibley with his wife, Carol Somersille, an obstetrician-gynecologist, and their two children, Lauren Somersille Sibley and Carl Somersille Sibley.
Janie Johnston

Sibley attended the Harvard School for Boys, an elite private school in North Hollywood. “We were a class of 120, and there were four African-Americans, which was more than usual,” Sibley said. “Two of them were from my neighborhood, and their fathers were also physicians.”

Sibley entered Harvard University as a pre-med student. In his junior year, he served as president of Harvard’s Percy Lavon Julian Science Organization, founded in 1972 to foster enthusiasm and interest in science, math and engineering among black students.

The founding faculty adviser of the organization was S. Allen Counter, PhD, a professor of neurology at Harvard and an influential mentor for Sibley. Counter died in 2017. “I had multiple meetings with Dr. Counter to talk about a career in science and medicine,” Sibley said. “And he helped us arrange for prominent African-American scientists and physicians to come speak to our group.”

Sibley found mentors among his classmates, too. “The African-American upperclassmen had told me that, if you’re pre-med, it was a good idea to try to get exposure to research and science,” he said. Based on that advice, he spent his summers working in research laboratories at the National Institutes of Health and completed the research for his honors thesis in the molecular biology lab of Tom Maniatis, PhD, at Harvard.

After just three years at Harvard, Sibley graduated in 1982 with honors and went on to the MD-PhD program at Johns Hopkins. He was drawn to Johns Hopkins for many reasons, including the opportunity to interact with cardiothoracic surgeon Levi Watkins Jr., MD, who had been the first black student to attend and integrate Vanderbilt Medical School, and who went on to be the first surgeon to successfully implant an automatic heart defibrillator in a human patient. 

At Hopkins, Sibley began to develop his research interests in gastrointestinal physiology. His doctoral thesis in biochemistry focused on insulin receptor gene regulation.

Making his mark at Stanford

Sibley completed his pediatrics residency at Harbor-UCLA Medical Center in 1993. His scientific pursuits ultimately drew him to a postdoctoral fellowship in pediatric gastroenterology at Stanford. Gary Gray, MD, professor of gastroenterology, was investigating the lactase enzyme protein and how the protein may be regulated differentially during maturation. But Gray’s group was just beginning to explore regulation of the lactase gene.

“Besides being a trained pediatrician, Dr. Sibley had a PhD in molecular biology, an area that was crucial for our research,” said Gray, now a professor emeritus. Gray’s lab included technicians, a research associate and postdoctoral scholars. “Sibley immediately displayed exceptional leadership skills. He’s just a spectacular human being — a humble, mature, quiet leader whom everyone was highly fond of.”

Gray supported Sibley’s application to the Robert Wood Johnson Foundation’s Minority Medical Faculty Development Program. An award from the program helped secure Sibley’s research time at 70 percent, which increased to 75 percent after he received a career development “K award” from the NIH shortly thereafter. Sibley went on to receive NIH research support for the next 20 years. Among other findings, Sibley’s laboratory characterized and was the first to demonstrate functionality for the DNA polymorphism associated with lactase persistence in humans.

Kenneth Cox, MD, now a professor emeritus of pediatric gastroenterology, joined Stanford as the division chief of pediatric gastroenterology in 1995, when Sibley was still a fellow, and worked with him for more than two decades. “In our division, Eric was the scientist who was involved with very basic research, which was important for our division. He helped us get NIH funding for our fellowship program and mentored our fellows for their research and academics, and many of them chose academic careers because of that experience,” Cox said. “Eric stands out as a model for the academic world in terms of being a basic researcher, a clinician and a mentor for other people who want to have that kind of career.”

Changing the pace

By 2011, Sibley needed more than crutches to keep going. He began using a wheelchair, and had an automatic door installed in his office at the School of Medicine. Around the same time, he was appointed an academic advising dean at the school. 

In an effort to slow progression of his multiple sclerosis, Sibley receives a six-hour, twice-yearly monoclonal antibody infusion therapy, a pioneering treatment developed at Stanford.
Mosese Ahomana

With about 475 students in the medical school at any one time, Sibley — one of four academic advising deans — supports between 110 to 120 students. “It ends up being possibly hundreds of one-on-one or group meetings with students over the course of the year, which is remarkable given that he’s also doing research and clinical practice,” said Neil Gesundheit, MD, MPH, professor of endocrinology and senior associate dean for medical education.

Sibley has a unique flair for supporting medical students, not only in routine academic, research and career guidance, but also when things aren’t going well. “Sometimes students who are struggling in school begin to isolate themselves. We call it cocooning,” Gesundheit said. “A student who is self-isolated because of not meeting a deadline starts to compound the problem by being ashamed that they haven’t met the deadline. This makes matters worse.” 

Sibley has a way of reaching out to those students sympathetically and putting them at ease, Gesundheit said. “He’ll say, ‘I know it’s hard for you to communicate back with me and maybe you’re a bit ashamed of what’s happened, but let’s just start over and get things moving in a positive direction.’ He’s excellent at that, at really disarming a student and helping them address those kinds of issues.”

With students who are the most vulnerable — those with physical or mental health challenges — Sibley found he could be the most helpful. “That’s one area where my own health issues have made it a little bit easier for students to approach for the support they need,” he said.

Gesundheit agreed. “He’s vulnerable, and he’s saying to you: If you’re vulnerable, I can understand that and help you.”

Mentoring the next generation

In the spring of 2018, Maïté Van Hentenryck, a first-year medical student, and her roommate Claire Rhee launched a group for medical students with disabilities and chronic illnesses. A blood infection when Van Hentenryck was a baby had resulted in the loss of her right leg and other orthopedic issues. Their new group would need an academic adviser to meet official requirements, and Van Hentenryck, who had been randomly paired with Sibley as her academic adviser, knew just whom to ask. 

“I reached out to Dr. Sibley to see if he’d like to be the group adviser,” Van Hentenryck said. “And he responded immediately that he’d be really happy to.” Rhee and Van Hentenryck were encouraged by Sibley’s participation and what it held for the group’s future. “I think he’s going to be a tremendous resource for us,” Van Hentenryck said.

Sibley had excelled in biomedical research, clinical care and education, but as a mentor and role model he provided something distinctive. Sibley could identify with students in ways that few other faculty could, and proved that there was a place for them in the highest ranks of medicine. 

“It’s inspiring to see someone who looks like me in a position I aspire to be in one day, especially because it’s so rare,” said Brian Boursiquot, a medical student at Stanford who is also African-American. “Dr. Sibley has helped me make important decisions about my academic pursuits and my choice of a clinical specialty.”

It’s inspiring to see someone who looks like me in a position I aspire to be in one day, especially because it’s so rare.

Sibley’s focus was also on advising fellows and aspiring physician-scientists in the pediatric gastroenterology department. Bass, who also worked closely with the fellows, heard from them about Sibley’s engagement in their work. “He comes to their research talks, he asks them hard questions. He’s fully engaged, and they’re quite aware of that,” Bass said. 

One of those fellows was Zachary Sellers, MD, PhD, now an instructor of pediatric gastroenterology at Stanford. “Eric opened up his lab to me and really allowed me to use all of his equipment and supplies as if they were my own, which has been beneficial to me in having a platform to perform research that is specific to my interest in gastrointestinal complications that occur in cystic fibrosis,” Sellers said. “I think in some ways it’s a kind of pay-it-forward from the mentorship that he received early on in his career.”

When she was new to Stanford Medicine’s faculty, Aida Habtezion, MD, associate professor of gastroenterology and hepatology, was interested in applying for the Robert Wood Johnson program, just as Sibley had done. “It’s nice when you find people who resemble you in many ways — as an African-American, a scientist and specifically a gastroenterologist — and who have been successful in the field that you are just starting. It gives you hope,” Habtezion said. “And the things that they tell you, the encouragement they give you, the support in how you should position yourself, what applications you should look at, how you should improve your CV. These are some examples of things you get from them, and they are invaluable. Eric was a very important mentor who could guide me and give me advice, because he walked that path before me.”

National recognition and responsibilities

Sibley’s efforts as an adviser and mentor at Stanford soon earned him national responsibilities, as well. In 2016, he was named the inaugural director of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition’s Mentoring Program for Investigative Junior Faculty. The program pairs assistant professors of pediatric gastroenterology with senior mentors at another institution to facilitate long-term mentorship affiliations. “In my communications with the leaders in the society, it is evident that Eric is deeply respected and admired — not just for his research, but also for his citizenship, generosity, teaching and mentoring,” said Mary Leonard, MD, professor and chair of pediatrics.

Sibley has also had to deal with setbacks and challenges. In October 2016, while transferring from his bed to his wheelchair, he fell and broke his leg. “Turns out I have osteoporosis from sitting instead of using my bones,” he said. “A lot of people who use wheelchairs get osteoporosis.”

The bone had to be set with a titanium rod that ran the length of his right femur. After his surgery, Sibley spent two weeks in a rehabilitation facility in Los Gatos. While he was there, Leonard called him to discuss two new departmental roles she hoped he would take: the inaugural associate chair for academic affairs, and liaison to the Office of Faculty Diversity and Development. 

Sibley, who had learned that a physical setback didn’t have to mean a professional one, was delighted to accept the positions.

Sibley’s professional progress seemed to be the inverse of his disease progression. One year later, he received the Distinguished Service Award from the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition. This past spring, in his 25thyear at Stanford, Sibley reached a long-awaited benchmark in his career: promotion to full tenured professor. He is the only African-American to begin his career as a postdoctoral scholar at Stanford Medicine and rise through the ranks to the highest faculty position. 

“Eric Sibley has shown an indomitable spirit both personally and professionally,” said Lloyd Minor, MD, dean of the School of Medicine. “Science can be unpredictable and at times discouraging, but Eric demonstrates that leading the biomedical revolution in precision health requires a revolutionary spirit. We at Stanford Medicine are very proud of his many accomplishments.” 

Even as he has become a nationally recognized mentor, he still remains an inspiration to his colleagues locally. For Bass, Sibley represents a standard of medical professionalism that he continually looks up to. “It’s the core of what we’re supposed to really be,” Bass said. “That often gets lost in flashy technology, and although you can get distracted from it easily, it’s about trying to help people, help them develop as much autonomy as they can, and being kind to fellow humans.”

For Sibley, prevailing through adversity had a lot to do with those who’d cleared the path ahead of him, and his awareness that he could do the same. “There were times later in my career when there was no one like me in a role ahead of me, no one to advise or mentor me,” he said. “So it was important to me to be that role model, to be a person students and colleagues with similar challenges could look to for guidance and encouragement.”

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