Change AD-Sync username attribute? Or change username in ITSM?

I synced an user group from our AD to ITSM and I think it used the sAMAccountName for username? Is it possible to change that to userPrincipalName or mail attribute instead? Or maybe the cn attribute to get the full name for a nicer looking user list but then the e-mail should be used for login and not username in ITSM.