Prince Frederik of Luxembourg, son of Prince Robert of Luxembourg and Princess Julie of Nassau, passed away on March 1, 2025. He died in Paris after a long fight with POLG mitochondrial disease, a rare and incurable genetic disorder. His death came just one day after Rare Disease Day.
Family’s Heartfelt Announcement
The POLG Foundation, which Frederik founded in 2022, confirmed his passing. Prince Robert shared the heartbreaking news in a statement on the foundation’s website.
“It is with a very heavy heart that my wife and I would like to inform you of the passing of our son, The POLG Foundation Founder and Creative Director, Frederik,” Prince Robert wrote.
Frederik said his final goodbyes to his loved ones in his unique way. Prince Robert recalled that his son left them with “some kind, some wise, some instructive” messages before departing with a final long-standing family joke.
A Touching Final Question
During his final moments, Frederik turned to his father and asked, “Papa, are you proud of me?”
Prince Robert described the moment as profound. He noted that Frederik had struggled to speak for several days, making the clarity of his words even more surprising.
The family’s statement beautifully captured Frederik’s legacy: “Though one light was extinguished in Paris on March 1, so many others remain, thanks to Frederik’s selfless work.”
Understanding POLG Mitochondrial Disease
POLG mitochondrial disease results from a mutation in the POLG gene. This mutation disrupts mitochondrial DNA replication, leading to organ failure over time. The disease weakens the body by gradually depleting cellular energy, much like a faulty battery that never fully recharges.
The disorder affects critical organs, including the brain, nerves, muscles, and liver. Symptoms vary but can include seizures, muscle weakness, liver dysfunction, and vision loss. Unfortunately, no cure or effective treatment exists to stop its progression.
In Frederik’s case, doctors diagnosed him at 14. By then, the disease had already begun affecting multiple organs.
Why Is POLG Disease So Hard to Treat?
Treating POLG mitochondrial disease is extremely difficult due to its complexity. The disorder impacts multiple organs differently in each patient, making early diagnosis rare.
Over 200 mutations in the POLG gene cause varying symptoms and severity. Some patients experience seizures, muscle weakness, and vision loss. Others suffer from hearing impairment, speech difficulties, or respiratory failure.
Experts stress that no approved treatment can halt the disease. As a result, patients like Frederik face progressive organ failure. Research shows that mitochondrial disorders affect one in 5,000 people worldwide, making POLG disease the second most common serious genetic disorder after cystic fibros
Frederik’s Fight for a Cure
Despite his illness, Frederik dedicated his life to raising awareness and funding research for POLG mitochondrial disease. In 2022, he established The POLG Foundation to accelerate research and develop potential treatments.
Prince Robert shared his son’s passion in a statement: “Frederik jumped at the opportunity to create a foundation to find a cure. Though he always made it very clear that he did not want this dreadful disease to define him, he nonetheless immediately identified with and helped define the mission of The POLG Foundation.”
Frederik personally participated in clinical trials, hoping to pave the way for future treatments. He worked with scientists across Europe and the U.S. to develop experimental cell models that could lead to medical breakthroughs.
A Legacy of Hope
Frederik also launched a special clothing line, MITO, to support POLG research. Renowned fashion designer Donna Karan encouraged the project. Even in his final days, Frederik remained deeply involved in its creative direction.
The royal family assured that The POLG Foundation will continue its work in Frederik’s honor. They pledged to fund further research and support families affected by mitochondrial diseases.
Prince Robert reaffirmed their commitment: “We will be resolutely focused on alleviating suffering for the POLG community and other conditions associated with mitochondrial diseases.”
He ended his message with a tribute: “Frederik knows that he is my superhero, as he is to all of our family and to so very many good friends. His superpower was his ability to inspire and lead by example.”
Frederik’s unwavering spirit and dedication will continue to inspire many. His legacy will shine brightly through the foundation he created and the lives he touched.