R. Michael Blaese, M.D.

It is with profound sorrow that we announce the passing of Dr. R. Michael Blaese, M.D., a trailblazing scientist whose work helped launch the era of human gene therapy. Mike died November 26, 2025, just a few months after the passing of his beloved wife of nearly 64 years, Julie. Their six-decade marriage was a remarkable love story. She was his companion in every sense; together they created a life filled with love, purpose, and warmth that extended to their family, friends, and the many scientists he worked with and mentored throughout his long career.

Mike’s career at the National Institutes of Health (NIH) started in the late 1960’s and spanned 33 years. He served as a senior investigator at the National Cancer Institute (NCI) and ultimately became Chief of the Clinical Gene Therapy Branch at the National Human Genome Research Institute (NHGRI).

As an immunologist, he was committed to understanding and treating primary immunodeficiency diseases. His expertise included rare disorders such as Wiskott-Aldrich syndrome (WAS) and Severe Combined Immunodeficiency (SCID). He was internationally recognized for his research in these rare diseases. He also was dedicated to helping patients and their families deal with the trial of having a rare disease by providing not only medical care, but support and compassion.

Mike was a mentor, and teacher to generations of scientists. Many credit him with shaping not only their careers but also their character; instilling in them a passion for caring for others and developing treatments that allow patients to live healthier lives.

Among his accomplishments, Mike was central to one of the most significant breakthroughs in modern medicine, the first approved human gene therapy treatment. In 1990, together with his NIH colleagues, he led the first clinical trial in which healthy copies of the gene encoding adenosine deaminase (ADA) were inserted into the T-cells of children with Severe Combined Immunodeficiency (SCID). The success of that trial marked the dawn of gene therapy as a tool to correct genetic disease in humans. Years later, the first gene therapy patients are living normal, healthy lives and thriving without the once-fatal infections of SCID.

Under his leadership the NIH gene-therapy program developed technologies that would lay the groundwork for subsequent clinical trials across cancer, metabolic disorders, and infectious diseases. He also co-invented a retroviral-based ex vivo gene-therapy approach, now foundational in the field.

Mike retired from the NIH in 2000, but he continued to advance care and research as Medical Director of the Immune Deficiency Foundation (IDF). His work supported patients, families, and research initiatives worldwide. The “Michael Blaese Research Grant,” created in 2022, stands as a testament to his ongoing influence on primary immunodeficiency research.

Alongside his scientific achievements, Mike was first and foremost a devoted husband, father, and grandfather with a gentle and warm spirit. He leaves behind two daughters: Elise (married to Rick Irving) and Kristianne (married to Paul Keyser), and five grandchildren: Giovanni, Katrina, Julianne, Roe, and Isabella. His love for Julie, his kindness, and his unwavering belief in the importance of family shaped every part of his life.

One of Mike’s great happinesses was spending time with his family and being in nature. He and Julie built a weekend house on Maryland's eastern shore of the Chesapeake Bay as a place of tranquility, relaxation and rejuvenation. The whole family cherished the time spent together in the natural beauty of the Chesapeake.

Mike’s passing marks the close of an extraordinary chapter in biomedical science. His pioneering insight and compassion helped transform gene therapy from speculative science into life-changing medicine. The first gene therapy patients continue to live full, healthy lives, their stories stand as living monuments to his work. His legacy endures in every life saved, every scientist inspired, and every advance built upon the foundation he helped create.

Further details regarding services will be available soon. If you wish, contributions can be made in his name to the Chesapeake Bay Foundation, https://www.cbf.org/; The Immune Deficiency Foundation, https://primaryimmune.org/; or Children with Diabetes, https://childrenwithdiabetes.com/.

Thank you to everyone for your thoughts and prayers for Mike and the Blaese Family.