Related Experiment Video
Updated: May 29, 2026

Modeling Myotonic Dystrophy 1 in C2C12 Myoblast Cells
Published on: July 29, 2016
DNA duplication associated with Charcot-Marie-Tooth disease type 1A
J R Lupski1, R M de Oca-Luna, S Slaugenhaupt
1Institute for Molecular Genetics, Baylor College of Medicine, Houston, Texas 77030.
Abstract:
Charcot-Marie-tooth disease type 1A (CMT1A) was localized by genetic mapping to a 3 cM interval on human chromosome 17p. DNA markers within this interval revealed a duplication that is completely linked and associated with CMT1A. The duplication was demonstrated in affected individuals by the presence of three alleles at a highly polymorphic locus, by dosage differences at RFLP alleles, and by two-color fluorescence in situ hybridization. Pulsed-field gel electrophoresis of genomic DNA from patients of different ethnic origins showed a novel SacII fragment of 500 kb associated with CMT1A. A severely affected CMT1A offspring from a mating between two affected individuals was demonstrated to have this duplication present on each chromosome 17. We have demonstrated that failure to recognize the molecular duplication can lead to misinterpretation of marker genotypes for affected individuals, identification of false recombinants, and incorrect localization of the disease locus.
Related Concept Videos
Polytene Chromosomes
Restarting Stalled Replication Forks
Gene Duplication and Divergence
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
Duplication of Chromatin Structure
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
Chromosome Duplication
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
Huntington Disease l: Introduction

