  We study the charge character of the Andreev bound states (ABSs) in
one-dimensional topological superconductors with spatial inversion symmetry
(SIS) breaking. Despite the absence of the SIS, we show a hidden symmetry for
the Bogoliubov de Gennes equations around Fermi points in addition to the
particle-hole symmetry. This hidden symmetry protects that the charge of the
ABSs is solely dependent on the corresponding Fermi velocities. On the other
hand, if the SIS is present, the ABSs are charge neutral, similar to Majorana
fermions. We demonstrate that the charge of the ABSs can be experimentally
measured in the tunneling transport spectroscopy from the resonant differential
tunneling conductance.
