  We present a parameter-free ab initio calculation of the $\alpha$-particle
monopole transition form factor in the framework of nuclear lattice effective
field theory. We use a minimal nuclear interaction that was previously used to
reproduce the ground state properties of light nuclei, medium-mass nuclei, and
neutron matter simultaneously with no more than a few percent error in the
energies and charge radii. The results for the monopole transition form factor
are in good agreement with recent precision data from Mainz.
