Gravitational uncertainties from dimension-six operators on   supersymmetric GUT predictions
  We consider the gravity induced dimension six terms in addition to the dimension five terms in the SUSY GUT Lagrangian and find that the prediction for $\alpha_s$ may be washed out completely in supersymmetric grand unified theories unless the triplet higgs mass is smaller than $ 7\times 10^{16} $ GeV. 
Alakabha Datta, Sandip Pakvasa and Utpal Sarkar