Derek Jeter On Signing Andy Pettitte's Son To Marlins Deal, 'He's Got Good Genes!'

Does a good fastball run in Pettitte blood? Derek Jeter is certainly hoping so ... 'cause the Marlins exec said he signed Andy Pettitte's son this week because he's banking on the kid's DNA!! Jeets spoke about the Marlins' deal with Jared Pettitte…