Cohen syndrome - a rare genetic cause of hypotonia in children.

Cohen syndrome is a rare, genetic condition, recessively inherited, associated with specific facial dysmorphism, global developmental delay, hypotonia and ophthalmic abnormalities. A delay in making the diagnosis commonly occurs, because of the lack of a definitive molecular test and also because of the clinical variability of the syndrome. In this paper we describe four cases of Cohen syndrome, together with a comparison with other cases reported in the literature, in order to further delineate this condition.