LDAP authentication and asp.net membership roles

I have an application that uses LDAP to authenticate a user. This works fine, except I want to implement the users from the LDAP into the standard asp.net membership database roles.
For instance:
user logs in with their domain account user is authenticated and is in a role that resides in the database asp.net membership tables. user has access to the application based on their role within the app. Is there a way to do this? What recommendations does one have to achieve this?
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