mtDNA from the mother/Mary could be compared to the son/Jesus to determine if they were actual mother and son. Other bones in the same burial would reveal DNA that could be compared to see if their relationship was family or, if not family, probably by marriage.
Descendants of Jesus' half-brothers (if you're Catholic you might not believe he had actual half-brothers) might also be a source for comparable DNA to link children to Mary's lineage.
In the film Jacobovici says six of the boxes, inscribed in Hebrew, Latin and Greek, bear the names Yeshua (Jesus) bar Josef (son of Joseph); Maria (a Latin form of Miriam, or Mary, in English); Matia (Hebrew for Matthew, a name common to the families of Mary and Joseph); Yose (a name identified as Jesusâ brother in the Gospel of Mark); Yehuda bar Yeshua (Judah, son of Joseph); and Mariamne e mara (Mariamne, known as the master. Mariamne was Mary Magdaleneâs real name, according to a Harvard professor).
Mitochondrial DNA samples were taken from the boxes ascribed to Jesus and Mariamne and tests were run at the Thunder Bay laboratory which prove the two people associated with the boxes were not maternally related and most likely married, concludes narrator Ron White. -
http://www.tbsource.com/Localnews/index.asp?cid=92871
It will be interesting to learn whether the DNA of all the sons of Mary from this tomb show that the sons all had the same father.
Jesus, being the product of the Holy Spirit and Mary, could be expected by those who believe in his divinity to have had unique DNA. Of course, if the bones of Jesus (born to Mary and Joseph of the New Testament) could be actually identified, then divinity as described in the New Testament gospels and letters would be out of the question.