Alex Rodriquez has previously admitted that he used PEDs from 2001-2003 when he was with the Texas Rangers, but has denied using them since.
Ryan Braun was suspended for 50 games after his 2011 NL MVP season, however Braun won an appeal and had the suspension lifted before it ever started.
Bartolo Colon was suspended for 50 games in 2012.
Gio Gonzalez is on the list of players connected to Biogenesis, but as previously reported by the Washington Post, he only received legal substances from the clinic.
The Miami New Times was the first to break the story about MLB's investigation into Biogensis which started in January. It is believed that MLB will look for 100 game suspensions for a handful of players, including Rodriquez and Braun, which would essentially end their seasons. If the suspensions are upheld, the scandal will be the largest in the history of professional American sports.