DNA results are wanted from descendants of each of Jacob Rosenberg's children, or as many as possible.
Have any descendants of Max (Mordechai) Bloom tested??
Have any descendants of any of his sons who used the surname "Rosenberg" tested?
Is there Y-DNA from any direct male descendants?
FamilyTreeDNA (familytreedna.com) is having their Black Friday Sale - Thru Nov. 30, the Family Finder Test is On Sale there for $39.
This is $20 less than the usual Sale Price, $40 less than the non-sale price.
Private , great-grandson of Max (Mordechai) Bloom , has tested through Ancestry. I don't know if he's also tested elsewhere nor if he has Y-DNA results available.
I just see him as <private> Bloom but do see that he is
son of Melvin Bloom -- son of Samuel Bloom -- son of Max (Mordechai) (Blum or Rosenberg) Bloom -- son of Jacob Rosenberg
So yes,apparently a direct male descendant of Jacob thru Jscob's son Max
He is not a Geni user. Private User are you by any chance in contact with him?