Bynoe-Gittens follows in the footsteps of Jadon Sancho, who was 17 when he left the Premier League giants for Dortmund in 2017.
Sancho departed City for a clearer path to first-team football and has become of the hottest properties in Europe after scoring 30 goals and setting up another 35 in 79 Bundesliga appearances.
"Jamie Bynoe-Gittens has joined us, and we are delighted to have him at in our youth set-up. He will initially play with the Under-19s," said Zorc.
"Our scouting department have done a fantastic job! He is a highly talented wide player, who will get the chance to develop at his own pace in our youth teams.
"We don't want expectations to be raised too high right from the start.
"He is still a year younger than Jadon was then… the hope is that at some point he will be promoted to the professional team."
Bynoe-Gittens becomes the third Englishman in Dortmund's ranks, alongside Sancho and 17-year-old playmaker Jude Bellingham.
The new addition will be delighted if he is able to make anything like the impact already enjoyed by his two compatriots.
Dortmund beat off competition from Manchester United to sign Bellingham from Championship side Birmingham this summer, and he has already made history in his short time at the club.
Handed his debut in his side's season opener against Duisburg in the DFB-Pokal, Bellingham found the net to become Dortmund's youngest-ever goalscorer.
Bynoe-Gittens will seemingly have to wait a little longer for that sort of involvement but with 17-year-old Giovanni Reyna also playing an important role of late, the first-team pathway is certainly there.