Perahps that indifference is why the Vatican insists upon Mary being born sinless ... but it is a crucial point in Catholicism yet never addressed just assumed.
IF none of Mary's DNA made up the embryonic Jesus then Mary carrying the Christ was not a violation of her marriage vows in betrothal to Joseph. If, on the other hand, her gamete was used in fabricating the embryonic Jesus, Mary would be joined to a Husband BEFORE fulfilling her marriage vows to Joseph. This little niggling factoid is ignored by catholics. Think about it; God does not violate His own given statutes.
However, if Mary was not born sinless and she gave her womb to carry the Christ and had none of her DNA mixed to build His body, she would not fit the catholic vagueness necessary to sustain the false narratives about Mary being exalted beyond her Truth. To catholiciism, it is not enough that Mary consented to carry the Child without violating her oaths to Joseph. That is not precious enough to catholicisism so that religion twists the Truth to fit their own empowerment, not exaltation of such a precious young woman as Mary really is.
Meant to ping you folks to the bit about Mary.
I think that's part of a very extensive narrative about Mary.