July 26 Highlights

Abstract

Lawson et al. describe the clinical features in three families with CMT2 associated with novel mutations in the mitofusin 2 gene, a common cause of axonal CMT (23% of cases). Affected individuals showed age-independent variability of expression, and clinical examination was more sensitive than electrophysiology in identifying patients. see page 197 The accompanying editorial by Mary M. Reilly places this newly characterized cause of CMT2 into context of CMT 1 and the 15 or more other causes of CMT 2. The GTPase, mitofusin 2 gene ( MFN2 ) (a gene encoding MFN2, a mitochondrial fusion protein), is the primary gene mutated in CMT2A. MFN2 mutations cause a classical CMT2 phenotype: distal predominant lower limb wasting and weakness, sensory loss, and hyporeflexia. An important clinical point identified by Lawson et al. is the greater sensitivity of the clinical examination in determining affected status vs neurophysiology—confirming the impression of clinicians evaluating CMT2. see page 186 Goh et al. found …