  In this paper, we use the latest results of the ultra-high accuracy 1S-2S
transition experiments in hydrogen atom to constrain the forms of the deformed
dispersion relation in the nonrelativistic limit. For the leading correction of
the nonrelativistic limit, the experiment sets a limit at an order of magnitude
for the desired Planck-scale level, thereby providing another example of the
Planck-scale sensitivity in the study of the dispersion relation in controlled
laboratory experiments. And for the next-to-leading term, bound has two orders
of magnitude away from the Planck scale, but it still amounts to the best
limit, in contrast to previously obtained bound in the nonrelativistic limit
from the cold-atom-recoil experiments.
