An in frame, lys236 deletion in the intracytoplasmic domain of myelin protein zero (MPZ) has recently been designated as a mutation possibly associated with C harcot-Marie-Toothdisease (CMT) but requiring further docu...An in frame, lys236 deletion in the intracytoplasmic domain of myelin protein zero (MPZ) has recently been designated as a mutation possibly associated with C harcot-Marie-Toothdisease (CMT) but requiring further documentation. In this r eport we present a detailed clinical, electrophysiological, and genotype correla tion in three generations of a family with the MPZ lys236del mutation and provid e further evidence that this mutation is associated with CMT. The MPZ lys236del mutationis associated with an autosomal dominant, adult onset CMT phenotype, wit h variable penetrance ranging from an asymptomatic state to foot deformities, pe dal numbness, and muscle cramps. Nerve conduction studies disclose intermediate range, somewhat non-uniform slowing of motor nerve conduction, which is accentu ated in forelimb rather than distal nerve segments. Based on the contrasting fin ding of entire lynormal conduction velocities (CV) in a genetically affected 15 year old in this family, it remains to be established whether CV slowing with th is mutation is progressive in life, a pattern that would contrast with CMT1a (PM P22 gene duplication).展开更多
文摘An in frame, lys236 deletion in the intracytoplasmic domain of myelin protein zero (MPZ) has recently been designated as a mutation possibly associated with C harcot-Marie-Toothdisease (CMT) but requiring further documentation. In this r eport we present a detailed clinical, electrophysiological, and genotype correla tion in three generations of a family with the MPZ lys236del mutation and provid e further evidence that this mutation is associated with CMT. The MPZ lys236del mutationis associated with an autosomal dominant, adult onset CMT phenotype, wit h variable penetrance ranging from an asymptomatic state to foot deformities, pe dal numbness, and muscle cramps. Nerve conduction studies disclose intermediate range, somewhat non-uniform slowing of motor nerve conduction, which is accentu ated in forelimb rather than distal nerve segments. Based on the contrasting fin ding of entire lynormal conduction velocities (CV) in a genetically affected 15 year old in this family, it remains to be established whether CV slowing with th is mutation is progressive in life, a pattern that would contrast with CMT1a (PM P22 gene duplication).