  Current neutrino oscillation data indicate the existence of two large lepton
mixing angles, while Kobayashi-Maskawa matrix elements are all small. Here we
show how supersymmetric SO(10) with extra chiral singlets can easily reconcile
large lepton mixing angles with small quark mixing angles within the framework
of the successful Fritzsch ansatz. Moreover we show how this is fully
consistent with the thermal leptogenesis scenario, avoiding the so-called
gravitino problem. A sizeable asymmetry can be generated at relatively low
scales. We present our results in terms of the leptonic CP violation parameter
that characterizes neutrino oscillations.
