Was the movie dreamgirls based on story about supremes?

Dreamgirls was loosely based on the history of The Supremes, but it also incorporated elements from other Motown acts and stories. The main character, Deena Jones, is similar to Diana Ross, but her career also has parallels with those of Florence Ballard and Mary Wilson. Other characters in the film are based on real-life Motown figures, such as Berry Gordy (Curtis Taylor Jr.), Smokey Robinson (Jimmy "Thunder" Early), and James Brown (James "Thunder" Early). However, the story is fictionalized and does not directly follow the history of The Supremes.