110th ENMC International Workshop: The congenital cranial dysinnervation disorders (CCDDs): Naarden, The Netherlands, 25–27 October, 2002

Abstract

A multi-disciplinary group of 13 clinicians and researchers from six countries convened for the first time to study a group of congenital neuromuscular diseases characterized by abnormal eye, eyelid, and/or facial movement. This group of diseases includes Duane syndrome, congenital fibrosis of the extraocular muscles (CFEOM), Möbius syndrome, horizontal gaze palsy, congenital ptosis and congenital facial palsy. Although these disorders were previously referred to in the literature under various terms, including ‘congenital fibrosis syndromes’, we have now chosen to refer to them as the ‘congenital cranial dysinnervation disorders’ or CCDDs. This name reflects our belief that these disorders result from developmental errors in innervation of the ocular and facial muscles. Thus far, members of the consortium have identified ten CCDD genetic loci and two CCDD disease genes (PHOX2A mutated in CFEOM2 and SALL4 mutated in Duane syndrome with radial ray anomalies). A CCDD classification scheme and an International CCDD Consortium have been established. The goals of the Consortium are to foster continuing research into the genetic basis of these disorders by identifying new families and affected individuals and by the sharing of genetic resources. Future studies of the CCDD genes should enhance our understanding of the pathophysiology and treatment of these disorders.