Well, to make a long story short, Debra Messing is Jewish!
Since Debra Messing's mother is Jewish, and in Orthodox Judaism and Conservative Judaism, those with a Jewish mother (or those who underwent a halakhic conversion) are considered Jewish, then that makes her Jewish. Her father is Jewish too.
Debra Messing (whose full birth name is Debra Lynn Messing) was born on August 15, 1968 in Brooklyn, New York, U.S..
She is known for her television roles as Grace Adler in Will & Grace. She also starred in The Starter Wife and Smash.
If you see any details that require update, please Let us know!