Mackenzie was born in Phoenix, Arizona. Being the daughter of Wellington “Megaton” Dias – one of the top BJJ black belts in the world – she started practicing Brazilian Jiu-Jitsu by the age of 3 with both her father and her stepmother Luciana Tavares, who is also a black belt. Being a natural at sports since a kid, Mackenzie started competing in jiu-jitsu´s adult division at the age of 14. With talent and her tuition being closely followed by her father and Royler Gracie, Mackenzie won the world championship in every belt on her way to black belt, a degree awarded to her by her father just before her 20th birthday. After succeeding in Brazilian Jiu-Jits she to start her career in MMA in 2016. In June 2019 Mackenzie became a mother, after giving to Moa. Dern will return to fight for the UFC, where she is still undefeated, on October 12th for UFC Fight Night in Tampa, Florida.