[stlnative]

maybe Stern's DNA may match up to some crime already in the database.

[Sacajaweau]

You never know. Maybe he pricked himself and there was a drop of blood on the sheet. Maybe THAT's why Perper wanted Anna's DNA AND it was allowed.

Despite the flap about "baby exchange", they take footprints, too. We knew that it's Anna's baby and no exchange possible.