  We study quark and electron EDMs generated by Yukawa couplings in
supersymmetric models with different gauge groups, using the EDM properties
under flavour transformations. In the MSSM (or if soft terms are mediated below
the unification scale) the one loop contributions to the neutron EDM are
smaller than in previous computations based on numerical methods, although
increasing as tan^3\beta. A neutron EDM close to the experimental limits can be
generated in SU(5), if tan\beta is large, through the u-quark EDM d_u,
proportional to tan^4\beta. This effect has to be taken into account also in
SO(10) with large tan\beta, where d_u is comparable to the d-quark EDM,
proportional to tan\beta.
