It is said that you just need to look to a child’s early interests and aptitudes to know their future. Young Daniel Claassen, was obsessed with music, so everyone knew what he would grow up to be — a professional musician, of course!
It’s true that Daniel graduated from the University of Georgia with a bachelor’s degree in music performance, having already played with the Macon, Savannah and Atlanta symphonies on weekends as an undergraduate. During medical school, he was part of the Augusta symphony and ballet orchestra, where he kept his study materials on the stand next to his music so he could work during breaks. Later, he would play a few nights a month for the Rochester, MN orchestra and then the Charlottesville, VA orchestras, as well as playing weddings and chamber music ‘gigs.’
But during his senior year in college, he had decided his career future lay elsewhere. While his mastery of Bach’s Six Suites for Viola might impress even a medical school admissions board, MCATs matter too. So, Daniel pursued a master’s degree in biochemistry to complete the course foundation needed to be a medical school candidate. Now 24, he entered The Medical College of Georgia.
During that time, he met Esther Miller, who had just graduated from Wheaton College and would become his life partner and wife. Esther supported them through the remaining three years of Daniel’s medical school by overseeing student affairs at the medical college.
Even before starting medical school, Daniel had an inkling he would pursue neuroscience, after working in mitochondrial disorders research as part of his master’s degree. Medical school rotations in neurology, where he encountered faculty that focused on the physical exam, patient experience, and translational research solidified this interest.
After graduation, the couple moved to Rochester, Minnesota, where a Mayo Clinic residency offered Dr. Claassen spectacular opportunities for neuroscience training, and research. Following four chilly but invaluable years there, the two returned to the Southeast, where Dr. Claassen earned his master’s degree in clinical research at the University of Virginia, focusing on movement disorders and cognition, while serving as an instructor of neurology.
Vanderbilt COE is Born
When the opportunity to join Vanderbilt University Medical Center arose, he had his sights set on developing a clinic that would serve patients with movement and cognitive symptoms. Over the next 14 years, Dr. Claassen would become a professor of neurology and division chief of behavioral and cognitive neurology. In 2012, he founded Vanderbilt’s Level 1 HDSA Huntington’s Disease Center of Excellence (COE), now one of the largest treating clinics in the country, helping over 500 patients and their families.
Over his career, he has had continuous grant support from the NIH, as well as grant funding from HDSA, CHDI, the Michael J. Fox Foundation and other foundations. His work has been published in numerous professional journals, and he has accepted even more invited lectures. He has taught and mentored graduate students, medical students and residents, and supervised mentees’ research, spanning a wide range of degenerative neurological diseases. He was responsible for setting up a robust clinical trial program at Vanderbilt, and developing the role of the clinical coordinator as an integral member of the program.
Creating Community
Dr. Claassen is a staunch advocate for bringing together people from all the various groups — research, patient care, and advocacy — that focus on fundraising and family support. Toward that end, he has been active in HSG for the past 12 years, serving on key committees and working groups, and as editor-in-chief of HD Insights.
In 2018, he developed what has become an annual Southeast Regional HD Symposium bringing interdisciplinary teams together to elucidate comprehensive treatment goals for HD patients.
During these symposiums, listeners enjoy his quiet, understated manner and his dry sense of humor. Importantly, he has a cut-to-the-chase way of corralling the stories, themes, data and opinions that are bandied about when hundreds of people meet to share ideas — and come out with actionable outcomes.
In a recent conference address, he described the Claassen family’s close ties with Covenant School in Nashville, and how the aftermath of the school shooting in 2023 affected that community and the nation, demonstrating what it means to share collective grief over where we are as a country that this could happen.
He also shared that in that same year, his clinic mourned the loss of a patient with HD who took his own life. Talking about the reality that you can’t always predict such tragedies is something most everyone in the HD world relates to. Just bringing this to the forefront provided connection and comfort.
Maybe it is the artist in him, but he is able to make poetry of fears and grief and hopes no one in the room is immune to, and that brings people who care about people with HD together, whatever their geography and role.
Eyes Forward
As the new HSG CEO, Dr. Claassen has left the gate at a full run, formulating his plans for leading the organization.
Jack Griffin, a longtime HD patient care advocate who has provided time and treasure to multiple HD groups, has known Dr. Claassen as a colleague and friend for nearly two decades. He remarks:
“This appointment to CEO of the Huntington Study Group recognizes all Daniel has accomplished to date. His new role at HSG will provide him with a platform to accomplish significant and needed improvements in both HD care and research efforts, which are linked together.”
Notes from the Clinic
A “Yes” Man
In August of 2024 (about two decades after completing residency at Mayo Clinic), Dr. Claassen found himself at a dinner his staff put together to bid him farewell as their division chief, and congratulate him on his new role as the head of the Huntington Study Group.
Some of these colleagues shared what best characterizes Dr. Claassen in his day-to-day clinic life.
“He’s been such a part of all of our careers,” said associate professor and neurologist at the Vanderbilt COE, Dr. Katherine McDonell. “It was just amazing, watching people in the room stand up and tell similar stories about how he took them in and just transformed their careers. He has touched so many people over the years.”
Dr. McDonell relates her own story as someone who benefitted from his sponsorship, starting 10 years ago.
“I went to Boston for my residency because they had a strong cognitive program, and I kind of thought I would stay there,” she said. “But then I also got really interested in movement disorders, and wondered, wouldn’t it be cool if I could do a fellowship where I studied both Parkinson’s-plus type syndromes and Huntington’s, since there is so much overlap? I was told they just couldn’t make that work, but they said, ‘I’ve heard of this guy, Daniel Claassen, down at Vanderbilt, who started a program doing that.’”
“So I came down to meet with him, and he said, ‘Yeah, we can do that. We don’t have that right now, but we can build it.’ He was just starting the center, and we had about 40 patients at the time. I was the first fellow that he took on. We’ve had several more since then, but for me, as the first, it was a really cool, tailor-made fellowship.”
COE neurologist and assistant professor Dr. Amy Brown later came to the COE as one of those movement disorder fellows.
“I had been working in the HD clinic, but two and a half years ago, I met Daniel for breakfast, and let him know I was interested in helping even more with research. I think even then he was thinking, how can I build up this center so that when I do transition somewhere else, this research doesn’t fall apart? I joined the staff, and now I’m active in research studies and supervising all these research coordinators. If I’m not my own PI, I’m an active sub-PI on several studies,” she said.
“I feel so lucky to continue in these efforts to offer to our patients. He is really into sponsoring junior faculty, and he did that for me with helping develop my research career. It’s easy to find a mentor, but it’s rare to find a sponsor, someone who will put your name out there to advance your career.”
Dr. Anna Pfalzer, a research assistant professor of neurology, said in her toast, “He never says no, he never turns you down on anything. He starts with yes, and then either gets you connected with the right person or makes a place for you to do the work you want to do, whether in the lab or elsewhere.”
“It’s been wonderful to see someone with the mindset to see a need, and be able to build something to meet that need, including the administrative work, the funding and finding the right people. I think you don’t see that a lot in academic neurology. People kind of come in and do the job they’re told to do, but for me, just being able to work with him to create something was a really cool thing to be a part of,” McDonell said.
Never Too Busy
Amy Wynn, a nurse practitioner, has perhaps spent the most time in clinic with Dr. Claassen.
“His style is to sit back and give patients his undivided attention. He takes the time to talk to them about what’s going on in life rather than running to the med list right away. He knows their hobbies and their stories really well, and he always makes a point of checking on how they are personally doing and how their family is doing,” she said.
“And he is a hugger,” she continues. “He might hug a patient and then give them his personal phone number. All this is why they love him. Also why my job of keeping him on schedule can be challenging!”
She adds, “He also manages to balance work and family life. I don’t know how he does everything he does, but he goes to his sons’ golf tournaments and after-school activities and everything. I think he wakes up at about four in the morning!”
Esther Claassen summarizes the consensus well. “The impact he’s had with these families has been pretty tremendous. I think they all feel like he is family — they know just how much he cares for him. He sees all that they go through. He isn’t living it firsthand, obviously, but he sees it firsthand. He gets calls at night and he is glad to go visit with patients, whether it’s at their home or nursing home. Anything he can do to just improve quality of life is a win for everybody — patient and caregivers alike.”
Dr. McDonell adds, “The talks that he gives at the meetings show that in spite of all the things that he does — the trials, the research, the administrative stuff — he hasn’t lost the heart of caring for patients and families. That’s the focus of everything that we do, and he reminds us of that constantly.”