title: X-linked recessive Charcot-Marie-Tooth neuropathy: clinical and genetic study.
abstract: We describe three families with X-linked recessive Charcot-Marie-Tooth (CMT) neuropathies. The disease phenotype in family 1 was characterized by infantile onset, weakness of lower legs, areflexia, pes cavus, and mental retardation (2 of 5 patients). The disease phenotype in families 2 and 3 was characterized by late onset, distal weakness, and normal intelligence. Hereditary spastic paraparesis was also present in the CMT patients of family 2. Thirty X-linked DNA markers were used for linkage studies. A maximum lod score of +3.48 was obtained by multipoint linkage analysis for the DXS16 locus mapped at Xp22.2 in family 1. In families 2 and 3, there was suggestion of linkage of Xq26 markers; the peak multipoint lod score for these 2 CMT families was 1.81, at DXS144. These results were suggestive of heterogeneity. The joint analysis including both regions (Xp22.2 and Xq26) provided evidence against homogeneity (chi 2 = 9.12, P less than 0.005).
authors.affiliation: Department of Pediatrics, University of Iowa Hospitals, Iowa City 52242.
authors.forename: V V
authors.initials: VV
authors.lastname: Ionasescu
authors.forename: J
authors.initials: J
authors.lastname: Trofatter
authors.forename: J L
authors.initials: JL
authors.lastname: Haines
authors.forename: A M
authors.initials: AM
authors.lastname: Summers
authors.forename: R
authors.initials: R
authors.lastname: Ionasescu
authors.forename: C
authors.initials: C
authors.lastname: Searby
mesh_terms: D002607:Charcot-Marie-Tooth Disease / Q000235:genetics*; D002874:Chromosome Mapping; D005260:Female; D005808:Genes, Recessive; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D008297:Male; D010375:Pedigree; D010641:Phenotype; D014960:X Chromosome
chemical_list: D005819:Genetic Markers