This truth is stranger than these fictions
Dan Brown, quite unwittingly I'm sure, has done us a great service - he has made known to the general population the existence of certain 'stories' about Jesus.
The Qur'an's portrayal of the 'Virgin Mary' and Brown's Da Vinci Code share a common genesis and will eventually meet up at the same destination.
How can this be? Well...a couple of millenia or so, ago, a thirst to know more about Jesus than the gospels revealed gave rise to the concoction of various 'fables'.
These 'fables' were tailored specifically to resonate with certain audiences and to meet perceived needs and prevailing 'expectations'. Naturally therefore, they were riddled with historical and other errors.
The Da Vinci Code and part of the Qur'an's 'Virgin Mary' story borrowed material from this 'fabled' library and, living up to time-honoured tradition, tailored their own 'fables' to resonate with certain audiences and to meet perceived needs and prevailing 'expectations'. Naturally therefore, they also are riddled with historical and other errors.
Being only a 'lending' library, however, these 'fables' based on 'fables' will eventually be called in by their rightful owner - the great 'fable' library of history.