  Results for neutrino flavor oscillations and neutrino mixing mechanisms,
obtained from the analysis of the Sudbury Neutrino Observatory (SNO), the
SuperKamiokande (SK), CHOOZ, KamLAND and WMAP data, are used to calculate the
effective neutrino mass relevant for the neutrinoless double-beta decay. The
observability of the decay of 76Ge is discussed within different light-neutrino
mass hierarchies and by presenting a systematics on the available nuclear
matrix elements.
