  A gauge $U(1)$ family symmetry is proposed, spanning the quarks and leptons
as well as particles of the dark sector. The breaking of $U(1)$ to $Z_2$
divides the two sectors and generates one-loop radiative masses for the first
two families of quarks and leptons, as well as all three neutrinos. We study
the phenomenological implications of this new connection between family
symmetry and dark matter. In particular, a scalar or pseudoscalar particle
associated with this $U(1)$ breaking may be identified with the 750 GeV
diphoton resonance recently observed at the Large Hadron Collider (LHC).
