How could Jesus be sinless with untainted, incorruptible blood?

Les explains that this is the basis of the doctrine of the virgin birth. He notes many cannot accept it, but it is part of salvation. He taught from Genesis, beginning with Eve, that the mother's blood never goes into the fetus; the mother's blood has nothing to do with the fetus. That comes only from the Father. He says this is a physiological fact, and it is the basis of the virgin birth of Christ, that He could be sinless, and that His blood was divine, untainted, and incorruptible. Had Mary's blood interchanged with the fetus while He was in the womb, that would not have been true. But physiologically, the blood of the mother never enters the blood of the little one. He mentions reading a cattle magazine about breeding experiments where the blood of the mother never enters the calf; the whole blood system of the fetus comes from the Father. He showed it to his wife. It's a scientific fact that the blood system comes from the Father, not the mother. That's why Scripture maintains Jesus did not have a human father, consequently He didn't have human blood, He had divine blood, and that's why the virgin birth is so basic to salvation.