She is a 1979 graduate of the Henry W. Grady College of Journalism and Mass Communication, University of Georgia.
Gentzler joined at NBC4 in 1989, after the departure of Dave Marash. She co-anchors the weekday 6pm and 11pm editions of News4 on WRC-TV (NBC4) in Washington, D.C. and is also the station's health reporter. Her reports have taken her around the world, including the Persian Gulf, Bosnia and Ecuador. Her health reports can usually be seen on News4 at 5pm, and other station newscasts. She is the on-air spokesperson for the station's successful NBC4 Health and Fitness Expo, held each January at the Washington Convention Center. She also made an appearance as herself on an episode of the NBC show The Event.
Gentzler anchored WRC's 6pm news alongside veteran anchor Jim Vance for 28 years – a partnership ended by Vance's death in July 2017.