  We present new medium resolution kinematic data for a sample of 21 dwarf
early-type galaxies (dEs) mainly in the Virgo cluster, obtained with the WHT
and INT telescopes at the Roque de los Muchachos Observatory (La Palma, Spain).
These data are used to study the origin of the dwarf elliptical galaxy
population inhabiting clusters. We confirm that dEs are not dark matter
dominated galaxies, at least up to the half-light radius. We also find that the
observed galaxies in the outer parts of the cluster are mostly rotationally
supported systems with disky morphological shapes. Rotationally supported dEs
have rotation curves similar to those of star forming galaxies of similar
luminosity and follow the Tully-Fisher relation. This is expected if dE
galaxies are the descendant of low luminosity star forming systems which
recently entered the cluster environment and lost their gas due to a ram
pressure stripping event, quenching their star formation activity and
transforming into quiescent systems, but conserving their angular momentum.
