John Gregory Guccion

Dr. John Gregory Guccion, 89, of Bethesda, Md., passed away on Christmas Day, December 25, 2025, following a distinguished life devoted to his family and to serving United States veterans in the Washington, DC metropolitan area.

Born in Cleveland, Ohio, on October 10, 1936, to Sam and Helen (Galla) Guccion, John attended St. Ignatius High School, where his passion for science and nature began to blossom at an early age. After completing his undergraduate biology degree at John Carroll University in 1958, John continued building his medical credentials at Georgetown University Medical School, graduating in 1962. He then completed his internship at Emory University in Atlanta and residency training in pathology at Duke University Medical Center. In 1964, John entered the U.S. Army and served at Fort Benning, Ga., for two years before returning to Georgetown to complete his pathology training. After a two-year stint with the Armed Forces Institute of Pathology, he accepted an offer to join the staff at the Washington Veterans Affairs Medical Center, where he spent the next 30+ years of his professional career before retirement.

John spent most of his career working in the specialized field of electron microscopy, using extremely high magnification to diagnose infectious diseases and tumors. In addition to being recognized as a national expert in electron microscopy, he was a renowned associate professor of pathology at George Washington University, where he taught medical students through lectures and small-group instruction. John also authored papers in multiple medical journals and delivered international medical conference presentations.

In addition to his professional work, John was an avid botanist, joining other like-minded individuals on forays around the country. A dedicated husband and father, John was a strong Catholic and believed firmly in living the spirit of Christmas all year. He loved his Wildwood Manor neighborhood home in Bethesda, where he resided for more than five decades.

John is survived by his son, John Samuel Guccion (Brandi) of Irving, TX, and daughters Erin Lovely (Jason) of Arlington, VA, and Mary Kate Ephraim (Brian) of Garrison, NY. He is also survived by his sister, Helene Mische, as well as many nieces, nephews, great-nieces, and great-nephews. John’s passing was followed by the death of his beloved wife of more than 50 years, Elizabeth Gibson Bordley Goldsborough Guccion, who passed away peacefully at their home on January 4, 2026.

Visitation and Funeral Mass for John were held on Monday, January 5, 2026, at Holy Cross Church in Garrett Park, Md. He was laid to rest at Gate of Heaven Cemetery in Silver Spring, Md.

In lieu of flowers, memorial contributions may be sent to the National Park Foundation at nationalparks.org.