I discuss a SUSY-GUT model with a non-Abelian discrete family symmetry that explains the observed hierarchical pattern of quark and lepton masses. This SO(10)(75) model predicts modied quadratic seesaw neutrino masses and mixing angles which are interesting for three reasons: i.) they oer a solution to the solar neutrino problem, ii.) the tau neutrino has the right mass for a cosmologically interesting hot dark matter candidate, and iii.) they suggest a positive result for the ! oscillation

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... ches by the CHORUS and NOMAD collaborations. However, the model shares some problems with many other predictive GUT models of quark and lepton masses. Well-known and once successful mass and angle relations, such as the SU(5) relation GUT b = GUT , are found to be in conict with the current experimental status. Attempts to correct these relations seem to lead to rather contrived models.