Interestingly, in today's strict judaistic sects a real Jew is one whose MOTHER was a Jew. They don't especially like conversions, and a Jewish mother is absolute genetic proof that the children are at least partially Jewish. Yes, I have heard that.
The 'Jewish blood' line goes through the mother not through the father.
I wonder if that is a late development, which would be interesting, since it would prepare for the Lord's rightful rule.
I'm sure of it. I had an army buddy, a Rabbi visit last week. He was all upset because their converts were being rejected by the orthodox. Then he got into the "mother" lineage test and got apoplectic.