Quark Family Discrimination and Flavour-Changing Neutral Currents in the SU(3)_C X SU(3)_L X U(1) Model with Right-Handed Neutrinos

Contributions of flavour-changing neutral currents in the 3 3 1 model with right-handed neutrinos to mass difference of the neutral meson system $\Delta m_P (P = K, D, B)$ are calculated. Using the Fritzsch anzats on quark mixing, we show that the third family should be different from the first two. We obtain a lower bound on mass of the new heavy neutral gauge boson as 1.02 TeV.