Namesakes
Nobel Prize Winners:
1 medicine
(medicine) Gregg L. Semenza 2019 
Notable Actors and Entertainers:
2 actors
Gregg Henry 1952-
Gregg Sulkin 1992-
Notable Musicians:
1 musician
Gregg Allman 1947-2017
Rock and Roll Hall-of-Famers:
2 musicians
Gregg Allman 1995 The Allman Brothers Band
Gregg Rolie 1998; 2017 Santana; Journey