If by Rome you mean the Catholic Church, sprung from the times of the Church Fathers, then yes. The Roman Catholic Church (or, more correctly for early medieval times and before, simply Catholic) did not suddenly arise from the dew replete with all her doctrine that we know today; nor did her ecclesiastical structure and authority. If you do not consider the Church Fathers and their immediate heirs as part of the "true Church", then who was? Certainly not the heresies of the time. "Doctrinal corruption", if you will, was a process.
There was also the problem that much of the medieval church simply was not equiped to propoagate its doctrine to the people. While some of said doctrine was quite sound, local parishes often did a miserable job of spreading it. And corruption was rampant, particularly at the time of the Reformers. These things, along with the general amaglation of bad doctrine, brought about the Reformation.
If you do not consider the Church Fathers and their immediate heirs as part of the "true Church", then who was? I couldn't consider them as such. Doctrinally speaking, or in any way, I don't see Rome as ever being a part of Biblical Christianity.