New distal marker closely linked to the fragile X locus.
We have isolated II-10, a new X-chromosomal probe that identifies a highly informative two-allele TaqI restriction fragment length polymorphism at locus DXS466. Using somatic cell hybrids containing distinct portions of the long arm of the X chromosome, we could localize DXS466 between DXS296 and DXS304, both of which are closely linked distal markers for fragile X. This regional localization was supported by the analysis, in fragile X families, of recombination events between these three loci, the fragile X locus and locus DXS52, the latter being located at a more distal position. DXS466 is closely linked to the fragile X locus with a peak lod score of 7.79 at a recombination fraction of 0.02. Heterozygosity of DXS466 is approximately 50%. Its close proximity and relatively high informativity make DXS466 a valuable new diagnostic DNA marker for fragile X.
Institute of Human Genetics, University of Amsterdam, The Netherlands.
T J
TJ
Hulsebos
B A
BA
Oostra
S
S
Broersen
A
A
Smits
B A
BA
van Oost
A
A
Westerveld
D000818:Animals; D015139:Blotting, Southern; D002460:Cell Line; D006224:Cricetinae; D015342:DNA Probes; D005260:Female; D005600:Fragile X Syndrome / Q000235:genetics*; D008040:Genetic Linkage; D005819:Genetic Markers / Q000235:genetics*; D006801:Humans; D006822:Hybrid Cells; D008126:Lod Score; D008297:Male; D010375:Pedigree; D012150:Polymorphism, Restriction Fragment Length
D015342:DNA Probes; D005819:Genetic Markers