Identification of CpG islands in a physical map encompassing the Friedreich's ataxia locus.
The Friedreich's ataxia locus has been previously assigned to chromosome 9q 13-21.1 by the demonstration of tight linkage to two anonymous DNA markers. MCT112 (Z greater than 80, theta = 0) and DR47 (Z greater than 50, theta = 0). The absence of recombination between these three loci has prevented the resolution of gene/probe order in this region, impeding strategies for gene isolation. We report physical mapping over a 4-Mb genomic interval, linking the markers MCT112 and DR47 on a common 460-kb NotI fragment and identifying 11 CpG islands in the 1.7-Mb interval most likely to contain the Friedreich's ataxia locus. Four of these islands were detected only by analysis of three YAC clones spanning a 700-kb interval including the MCT112/DR47 cluster. Without clear evidence of the precise location of the disease locus from recombination events, each of these regions must be considered as specifying a potential "candidate" sequence for the mutated gene.
Wilkes
D
D
Department of Biochemistry and Molecular Genetics, St. Mary's Hospital Medical School, London, England.
Shaw
J
J
Anand
R
R
Riley
J
J
Winter
P
P
Wallis
J
J
Driesel
A G
AG
Williamson
R
R
Chamberlain
S
S
D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9; D003001:Cloning, Molecular; D015226:Dinucleoside Phosphates / Q000235:genetics*; D005621:Friedreich Ataxia / Q000235:genetics*; D006801:Humans; D015183:Restriction Mapping
D015226:Dinucleoside Phosphates; C015772:CpG dinucleotide