The Higgs boson is unified with gauge fields in the gauge-Higgs unification.
The SO(5) x U(1) gauge-Higgs electroweak unification in the Randall-Sundrum
warped space yields almost the same phenomenology at low energies as the standard model,
and gives many predictions for the Higgs couplings and new W', Z' bosons around
6 to 8 TeV, which can be tested at 14 TeV LHC.
The gauge-Higgs grand unification is achieved in SO(11) gauge theory.
It suggests the existence of the sixth dimension (GUT dimension)
in addition to the fifth dimension (electroweak dimension).
The proton decay is naturally suppressed in the gauge-Higgs grand unification.