Clustering of CMT1A duplication breakpoints in a 700 bp interval of the CMT1A-REP repeat.
The CMT1A-REP repeat is proposed to mediate unequal crossover leading to a 1.5 Mb duplication in chromosome 17p11.2-12 associated with Charcot-Marie-Tooth neuropathy type 1A (CMT1A). There is an apparent recombinational "hotspot" in the CMT1A-REP repeat since the majority of crossover breakpoints for CMT1A are located within a 1.7 kb interval. Further to characterize the crossover breakpoint region, we constructed PCR primers that specifically amplify the duplication breakpoint junctions in a series of Japanese and Caucasian CMT1A patients. We mapped the breakpoints in 89% of patients within a 700 bp interval of the CMT1A-REP repeat. This 700 bp region is 1.3 kb telomeric to a previously described mariner-like transposable element. Our observations further define the location of crossovers for CMT1A and provide additional evidence that this region is a recombinational "hotspot" within the CMT1A-REP repeat.
Yamamoto
M
M
Department of Neurology, Nagoya University School of Medicine, Japan.
Keller
M P
MP
Yasuda
T
T
Hayasaka
K
K
Ohnishi
A
A
Yoshikawa
H
H
Yanagihara
T
T
Mitsuma
T
T
Chance
P F
PF
Sobue
G
G
D044466:Asian People; D002607:Charcot-Marie-Tooth Disease / Q000235:genetics*; D019457:Chromosome Breakage / Q000235:genetics*; D002874:Chromosome Mapping; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D004252:DNA Mutational Analysis; D006801:Humans; D005810:Multigene Family / Q000235:genetics*; D011995:Recombination, Genetic / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D044465:White People