PROBES FOR DETECTION OF THE FRAGILE X SYNDROME

摘要

A polynucleotide selected from nucleic acid fragments (i) to (vii), polynucleotide sections thereof and nucleic acids hybridisable thereto; wherein each of the said nucleic acid fragments (i) to (vii) is hybridisable to at least part of the FRAXE region of the human chromosome, wherein the said FRAXE region comprises a proximal (CA)m repeat where m is a positive integer, a distal (CA)n repeat where n is a positive integer and therebetween a CpG island and a (GCC)p repeat wherein p is at least 3, and wherein said nucleic acid fragments (i) to (vii) are defined as follows: (i) a Hind III fragment, Hind IIIa, which fragment hybridises to that part of the FRAXE region of the human X chromosome which includes the GCC repeat, as illustrated in SEQ. ID. No. 1; (ii) an EcoRI fragment, EcoRIa, which fragment hybridises to that part of the FRAXE region of the human chromosome which includes the GCC repeat, as illustrated in SEQ. ID. No. 1; (iii) an EcoRI fragment, EcoRIb, which fragment hybridises to that part of the FRAXE region of the human X chromosome which is distal to and overlapping with the Hind IIIa fragment defined in (i) above; (iv) an EcoRI fragment, EcoRIc, which fragment hybridises to that part of the FRAXE region of the human X chromosome which includes the proximal (CA)m repeat; (v) a Hind III fragment, Hind IIIb, which fragment hybridises to that part of the FRAXE region of the human X chromosome which includes the distal (CA)n repeat; (vi) a fragment, OxE 20, which comprises bases 1116 to 1974 of SEQ. ID. No. 1; (vii) a fragment, OxE 18, which fragment is bounded by an EcoRI site at its proximal limit and a Not1 site at its distal limit, and which hybridises at a site within the FRAXE region of the human X chromosome which is overlapping with and proximal to the CpG island; said nucleic acid fragments (i) - (vii) being substantially free of other nucleic acid fragments.