Mutation testing in Charcot-Marie-Tooth neuropathy.
In order to determine the optimal approach for mutation testing in the form of Charcot-Marie-Tooth (CMT) neuropathy, consecutive patients with a CMT phenotype, available family history information on at least first-degree relatives, and median motor conduction velocities of less than 50 m/sec were tested for the CMT1A duplication and for connexin32, peripheral myelin protein 22 (PMP22) and myelin protein zero (P0) point mutations. A cutoff value for median motor conduction velocity of less than 50 m/sec was adopted to include all CMTX families. All of the connexin32 mutations, except for one sporadic case, were found by first selecting families with no male-to-male inheritance of CMT and neurophysiological indicators of CMTX. All PMP22 and P0 mutations were found by selecting Dejerine-Sottas cases or dominantly inherited CMT1 with a very severe phenotype. It is concluded that "blind" testing of CMT1 families for connexin32, P0, and PMP22 mutations is of limited value.
Nicholson
G A
GA
University of Sydney, Molecular Genetics Laboratory, Concord Hospital, NSW, Australia. molmed@medicine.su.oz.au
D002607:Charcot-Marie-Tooth Disease / Q000175:diagnosis* / Q000235:genetics*; D017630:Connexins / Q000235:genetics*; D005260:Female; D020440:Gene Duplication; D005799:Genes, Dominant; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D008297:Male; D018993:Myelin P0 Protein / Q000235:genetics*; D009185:Myelin Proteins / Q000235:genetics*; D017354:Point Mutation; D014960:X Chromosome; D000097002:Gap Junction beta-1 Protein
D017630:Connexins; D018993:Myelin P0 Protein; D009185:Myelin Proteins; D000097002:Gap Junction beta-1 Protein; C073687:PMP22 protein, human