WMAP dark matter constraints on b-τ Yukawa unification with massive neutrinos

We revisit the WMAP dark matter constraints on b - tau Yukawa Unification in the presence of massive neutrinos. The large lepton mixing indicated by the data may modify the predictions for the bottom quark mass, enabling Yukawa unification also for large tan beta, and for positive mu that was previously disfavoured. As a result, the allowed parameter space for neutralino dark matter increases for positive mu, particularly for areas with resonant enhancement of the neutralino relic density. On the contrary, a negative mu is not easily compatible with large lepton mixing and Dirac neutrino Yukawa couplings, and the WMAP allowed parameter space is in this case strongly constrained.