Also, this is a usage note from the dictionary.com entry

—Usage note
Comprise has had an interesting history of sense development. In addition to its original senses, dating from the 15th century, “to include” and “to consist of” (The United States of America comprises 50 states), comprise has had since the late 18th century the meaning “to form or constitute” (Fifty states comprise the United States of America). Since the late 19th century it has also been used in passive constructions with a sense synonymous with that of one of its original meanings “to consist of, be composed of”: The United States of America is comprised of 50 states. These later uses are often criticized, but they occur with increasing frequency even in formal speech and writing.

In the commonwealth countries that follow the Queen’s English, ‘comprised of’ in the passive voice has become largely accepted, though American linguists continue to frown upon it.

Last but not the least… probably, “comprise” does not need any “of”…thus let the “of” be “off”…

With all my good wishes..