According to TrekMovie.com:
Today is another sad day for Trek fans, TrekMovie was just informed by the Roddenberry family that Majel Barrett Roddenberry passed away this morning at the age of 76. The first lady of Star Trek’ died of leukemia at her home in Bel Air. At her side were her son Eugene ‘Rod’ Roddenberry along with family and friends.
Majel Barrett began her career in the 1950’s with roles in such popular shows as “Leave it to Beaver,” “Bonanza” and “The Lucy Show; but it was her numerous roles in the legendary Star Trek franchise that fans came to know and love her. Roddenberry had featured roles in almost every Star Trek television and film entity and became an iconic figure within the fan community. Her roles included Nurse Chapel in Star Trek: The Original Series, Lwaxana Troi in Star Trek: The Next Generation and the voice of the USS Enterprise computer in almost every incarnation of the series. However, it was the love affair between her and the late Star Trek creator Gene Roddenberry that earned her the title “The First Lady of Star Trek.” Over the course of their more then quarter-century love affair, she became not only Gene’s partner, but also his creative muse. Roddenberry helped Gene expand the Star Trek universe and was an integral part of its continued legacy after his death. Majel recently completed reprising her role as the voice of the USS Enterprise for J.J. Abrams’ new Star Trek film.