If a gauge invariant quantum field theory (QFT) has a Lie group gauge invariance, the matter fields are defined in the fundamental representation of the group, and the gauge fields are defined in the adjoint representation of the group. If both representations are non trivial, the quantum fields in both representations carry the gauge charges. In the case of the U(1) group the adjoint representation is trivial, therefore the gauge field (photon) is also defined in the fundamental representation. Here only the matter field (electron) carries gauge charge (coulomb charge) and the gauge field does not carry gauge charge. In other words the photon is electrically neutral.