ABSENCE OF MUTATIONS IN PERIPHERAL MYELIN PROTEIN-22, MYELIN PROTEIN ZERO, AND CONNEXIN-32 IN AUTOSOMAL RECESSIVE DEJERINE-SOTTAS-SYNDROME

Motor and sensory neuropathies with the clinical features of HMSN III (Dejerine-Sottas syndrome, DSS) are etiologically related to heterozyg ous mutations in either peripheral myelin protein-22 (PMP22) or myelin protein zero (MPZ). Heterozygous mutations in either of these two gen es are also responsible for other hereditary peripheral neuropathies ( HNPP, CMT1A, CMT1B or CH). In two families DSS was related to the homo zygous presence of a MPZ mutation while heterozygosity showed a much m ilder phenotype. It has therefore been suggested that the clinical phe notype in peripheral neuropathies is related to the mutated gene, the type of mutation and confounding effects from other sources. In this s tudy we describe a family with recessive DSS in which mutations were a bsent from the PMP22, MPZ, and connexin 32 (Cx32) genes. We conclude t hat DSS also exists as a distinct genetic entity with autosomal recess ive inheritance as originally defined by Dejerine and Sottas in 1893. (C) 1998 Elsevier Science Ireland Ltd.