Personal History
She was born in the borough of Queens.
Work History
Trivia
"To Jo Duffy with love"
- In Iron Man #103 (October 1977), a character named Jo Duffy appears. She shares name with this real-life Mary Jo Duffy, writer and editor for Marvel Comics, and both of them seem to work for "the Bullpen." However, the real Duffy started working for Marvel in 1978, about a year after the publication of this comic - possibly because in 1977 she already worked for Marvel in uncredited positions. She was, however, involved with Marvel as a letter writer prior to 1978.