Why do some Catholic bibles translate Genesis 3:15 as Mary crushing the head of the serpent?Answer:
The problem here is the Hebrew vowel pointing, which was not part of the original inspired Hebrew. Vowel pointing was added in the 9th century AD for easier reading. As such, Genesis 3:15 will read as "he" or "she" depending on where the vowel pointing is placed. The reading of "he" is caused by placing the vowel point inside the Hebrew letter WAW, and the whole word is thus pronounced in Hebrew as HUAH, or close to that, whereas the reading "she" is caused by placing the vowel point underneath the Hebrew letter HE, and the whole word is thus pronounced HIUAH, or HIWAH, or close to that. In any case, without the vowel pointing, we don't know what the gender of the pronoun is. Jerome thought he knew based on what he knew of the Hebrew language and the information he had in Tradition, and thus he translated it as "she." Since he was closest to that time period, he is generally accepted as the authority on the subject, although he has been known to make mistakes.
Catholic Apologetics International
November 7, 2001 A.D.