Phenomenological implications of two simple modifications to Tri-Bimaximal mixing

We study the phenomenological implications of breaking the Tri-Bimaximal (TBM) mixing in such a way that either first or second column of TBM mixing matrix remains invariant. We present two such textures and confront them with the experimental data. We give the predictions of these textures for atmospheric mixing angle $\theta_{23}$ and Dirac-type CP violating phase $\delta$ that will be measured in the future experiments.