  A discrete symmetry between quarks and (generalized) leptons can exist in
nature, and its spontaneous symmetry breaking scale can be as low as a few TeV.
Such a discrete symmetry also has interesting implications for how electroweak
symmetry is spontaneously broken, because the simplest version of the theory
requires two electroweak Higgs doublets rather than one in order to provide
acceptable values for quark and lepton masses. The effective theory generated
at electroweak-scale energies is thus a particular type of two-Higgs-doublet
model. We point out in this paper that the broken discrete symmetry imposes
very interesting constraints on the form of the Yukawa couplings between
physical Higgs bosons and quarks and leptons. In particular, we find that the
flavour-changing neutral Higgs couplings to down-sector quarks are proportional
to the neutrino Dirac mass matrix. If neutrinos are Dirac particles, then the
severe experimental upper bounds on their mass values renders tree-level
neutral flavour-changing Higgs effects on down-quark systems like
$K^0-\bar{K}^0$ negligibly small. We also discuss minimization of some relevant
Higgs potentials and some other pertinent phenomenological issues.
