Molecular Genetic Analyses of Charcot-Marie-Tooth Disease Type 1A in Korean

ABSTRACT

BACKGROUND: Charcot-Marie-Tooth disease type 1A (CMT1A) is an autosomal dominant inherited demyelinating peripheral neuropathy characterized by progressive distal muscular atrophy and marked slowing of nerve conduction velocities. A 1.5 Mb DNA duplication within chromosome 17p11.2-p12 has been reported. This disease appears to be caused by an altered copy number of the PMP-22 gene within the critical region. METHODS: DNA analysis was carried out for 158 persons from 40 unrelated families. PCR was done by D17S122 and D17S261. The DNA of the patients was ana-lyzed to detect three alleles for the presence of duplication. RESULTS: CMT1A duplication was found in 7 families (64%) of the patients with CMT1 by D17S122, but not by D17S261. CONCLUSIONS: We have found seven families of Charcot-Marie-Tooth disease type 1A with chromosome 17p11.2-p12 duplication by D17S122. We recommend the screening test by D17S122 for the detection of CMT1A in Korean because genetic analysis done by D17S261 was not informative.