  We consider non-renormalizable interaction term as a perturbation of the
conventional neutrino mass matrix. Quantum gravitational (Planck scale )effects
lead to an effective $SU(2)_L\times U(1)$ invariant dimension-5 Lagrangian
involving neutrino and Higgs fields,On symmetry breaking, this operator gives
rise to correction to the neutrino masses and mixing. The gravitational
interaction $M_X=M_{pl}$ which gives rise to additional terms in neutrino mass
matrix. We also assume that, just above the electroweak breaking scale,
neutrino masses are nearly degenerate and their mixing is Co-bimaximal mixing
by assuming mixing angle $\theta_{13}\neq0 = 10^{o}$,
$\theta_{23}=\frac{\pi}{4}$, $\tan\theta_{12}^ 2 =
\frac{1-3sin\theta_{13}^2}{2} = 34^{o}$ and Dirac phase
$\delta=\pm\frac{\pi}{2}$.There additional term can be considered to be
perturbation of the GUT scale Co-bimaximal neutrino mass matrix. The relation
consider with solar and atmospheric neutrino oscillation data predicted above
GUT scale $m_1' \simeq 0.00001eV-0.00003eV$, $m_2' \simeq 0.00008eV-0.00012$,
and $m_3' \simeq 0.000207eV-000320eV$.
