title: Mapping of DNA markers close to the fragile site on the human X chromosome at Xq27.3.
abstract: We report the identification of a new RFLP detected by the DNA probe MN12, which is linked to both the fragile site on the X chromosome at Xq27.3 and the highly polymorphic locus detected by St14 (DXS52). In situ mapping confirms the localisation of MN12 distal to the fragile site. A detailed physical analysis of this region of the X chromosome using pulsed-field gel electrophoresis has shown that MN12, St14 and DX13 (DXS15) are physically linked within a region of 470kb. A long range restriction map around the MN12 locus reveals at least two candidate HTF islands, suggesting the existence of expressed sequences in this region.
mesh_terms: D001483:Base Sequence; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D005260:Female; D006801:Humans; D008297:Male; D009693:Nucleic Acid Hybridization; D009710:Nucleotide Mapping; D010375:Pedigree; D010957:Plasmids; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D014960:X Chromosome