Nitesh,
Yes, we do transport the profiles from DEV to QA. One of the steps we perform before assigning the roles to test users in QA is to verify/validate that the transport moved over to QA successfully. Once the transports are verified as being successfully moved into QA, role assignments occur.
We are seeing the isssue of roles going ungenerated within PROD on roles that have resided in PROD for quite some time without any recent updates. {how's that for a twist 
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