title: Identification of CpG islands in a physical map encompassing the Friedreich's ataxia locus.
abstract: 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.
authors.affiliation: Department of Biochemistry and Molecular Genetics, St. Mary's Hospital Medical School, London, England.
authors.forename: D
authors.initials: D
authors.lastname: Wilkes
authors.forename: J
authors.initials: J
authors.lastname: Shaw
authors.forename: R
authors.initials: R
authors.lastname: Anand
authors.forename: J
authors.initials: J
authors.lastname: Riley
authors.forename: P
authors.initials: P
authors.lastname: Winter
authors.forename: J
authors.initials: J
authors.lastname: Wallis
authors.forename: A G
authors.initials: AG
authors.lastname: Driesel
authors.forename: R
authors.initials: R
authors.lastname: Williamson
authors.forename: S
authors.initials: S
authors.lastname: Chamberlain
mesh_terms: 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
chemical_list: D015226:Dinucleoside Phosphates; C015772:CpG dinucleotide