1043-3155 Pediatr Neurol Briefs pedneurbriefs Pediatr Neurol Briefs Pediatric Neurology Briefs Pediatr Neurol Briefs 2166-6482 1043-3155 2166-3155 Pediatric Neurology Briefs Publishers Chicago, IL, USA PNB-6-44-a 10.15844/pedneurbriefs-6-6-5 Neuromuscular Diseases Neurology Pediatrics Nervous System Diseases Child Development Brain Diseases Neurosurgery Child Infant Hereditary Motor and Sensory Neuropathy Mutation http://orcid.org/0000-0002-0173-7931 Millichap J. Gordon MD 1 2 * Division of Neurology, Children's Memorial Hospital, Chicago, IL Departments of Pediatrics and Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL Correspondence: Dr. J. Gordon Millichap, E-mail: jgmillichap@northwestern.edu 06 1992 01 07 2016 6 6 44 44 Copyright: © 1992 The Author(s) 1992 This work is licensed under the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. De-novo mutation in hereditary motor and sensory neuropathy type I

A duplication in chromosome 17 responsible for most cases of autosomal dominant HMSN 1 was present as a de-novo mutation in 9 out of 10 sporadic patients examined at the Department of Neurology, Academic Medical Center, Amsterdam, The Netherlands.

 De-Novo Mutation Autosomal Recessive Genetic Loci

A duplication in chromosome 17 responsible for most cases of autosomal dominant HMSN 1 was present as a de-novo mutation in 9 out of 10 sporadic patients examined at the Department of Neurology, Academic Medical Center, Amsterdam, The Netherlands. [1]

COMMENT. The previous assumption that isolated cases of HMSN I are most frequently autosomal recessive appears to be incorrect and testing for the duplication in chromosome 17 is essential to establish the mode of inheritance for genetic counseling of isolated patients.

This duplication of part of chromosome 17 was found in affected individuals from 7 of 8 families with HMSN I. Patients with HMSN type II do not show the duplication. [2]

HMSN type I also known as Charcot-Marie-Tooth disease type I is known to be genetically heterogeneous. At least 5 genetic loci have been identified including 3 dominant genes and 2 X-linked recessive genes. Ionasescu VV et al. from the Department of Pediatrics, University of Iowa Hospitals, Iowa City and the Massachusetts General Hospital present a clinical and genetic linkage study of 8 families with X-linked dominant Charcot-Marie-Tooth neuropathy which supports a localization of the diseased gene between DXS14 and DXYS1. [3]

 Hoogendijk JE Hensels GW Gabreels-Festen AA Gabreels FJ Janssen EA de Jonghe P De-novo mutation in hereditary motor and sensory neuropathy type I Lancet 1992 May 2 339 8801 1081 1082 10.1016/0140-6736(92)90668-S 1349106 Hallam PJ Harding AE Berciano J Barker DF Malcolm S Duplication of part of chromosome 17 is commonly associated with hereditary motor and sensory neuropathy type I (Charcot-Marie-Tooth disease type 1) Ann Neurol 1992 May 31 5 570 572 10.1002/ana.410310518 1596093 Ionasescu VV Trofatter J Haines JL Ionasescu R Searby C Mapping of the gene for X-linked dominant Charcot-Marie-Tooth neuropathy Neurology 1992 Apr 42 4 903 908 10.1212/WNL.42.4.903 1565250