title: Large scale physical mapping in the q27 region of the human X chromosome: the coagulation factor IX gene and the mcf.2 transforming sequence are separated by at most 270 kilobase pairs and are surrounded by several 'HTF islands'.
abstract: In spite of the large amount of genetic data obtained on the X chromosome and of the availability of many cloned sequences little is known about the physical map of this chromosome. The construction of large-scale restriction maps is now possible with pulsed field gel methods and data has recently been obtained in the region of band Xq28. We present here results of physical mapping in the Xq27 region, i.e. proximal to the fragile site at Xq27.3 associated with mental retardation, and show physical linkage between the coagulation factor IX gene and the mcf.2 transforming sequence recently localized to Xq27. Our data also indicate partial methylation of some sites in this region, and locate several 'HTF islands', i.e. CpG-rich, unmethylated sequences, containing several sites for 'rare cutter' enzymes, which are believed to be associated with expressed 'housekeeping' genes.
authors.affiliation: Centre d'Immunologie INSERM-CNRS de Marseille-Luminy, France.
authors.forename: C
authors.initials: C
authors.lastname: Nguyen
authors.forename: P
authors.initials: P
authors.lastname: Pontarotti
authors.forename: D
authors.initials: D
authors.lastname: Birnbaum
authors.forename: G
authors.initials: G
authors.lastname: Chimini
authors.forename: J A
authors.initials: JA
authors.lastname: Rey
authors.forename: J F
authors.initials: JF
authors.lastname: Mattei
authors.forename: B R
authors.initials: BR
authors.lastname: Jordan
mesh_terms: D001482:Base Composition; D002460:Cell Line; D002874:Chromosome Mapping; D004262:DNA Restriction Enzymes; D005164:Factor IX / Q000235:genetics*; D005600:Fragile X Syndrome; D005796:Genes; D006801:Humans; D006822:Hybrid Cells / Q000166:cytology; D008297:Male; D009693:Nucleic Acid Hybridization; D012729:Sex Chromosome Aberrations; D014170:Transformation, Genetic; D014178:Translocation, Genetic; D014960:X Chromosome
chemical_list: D005164:Factor IX; D004262:DNA Restriction Enzymes