A Relation between theta-13 and the Leptonic Dirac CP Phase in SO(10) Lopsided Models

It is shown that in SO(10) models where the large solar and atmospheric neutrino angles come from the charged-lepton mass being "lopsided", there is a characteristic relation between the 13 mixing angle of the neutrinos and the size of the Dirac CP- violating phase in the lepton sector. This is illustrated in a recently proposed realistic and predictive model.