Unusual X chromosome inactivation in a mentally retarded girl with an interstitial deletion Xq27: implications for the fragile X syndrome.
A de novo interstitial deletion (X)(q27.1q27.3), between the loci DXS 105 and F8, has been found in a mentally retarded female. The deleted X chromosome is preferentially early replicating in fibroblasts, B cells and T cells, suggesting that the missing region plays a role in inactivation of the X chromosome. None of the available DNA probes except DXS 98 maps to the deleted region of about 10,000 kb. The locus FRAXA is either included in the deletion, or located close to the distal break point.
Schmidt
M
M
Murdoch Institute, Royal Children's Hospital, Melbourne, Victoria, Australia.
Certoma
A
A
Du Sart
D
D
Kalitsis
P
P
Leversha
M
M
Fowler
K
K
Sheffield
L
L
Jack
I
I
Danks
D M
DM
D015139:Blotting, Southern; D002675:Child, Preschool; D002871:Chromosome Banding; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D004261:DNA Replication; D004303:Dosage Compensation, Genetic; D005260:Female; D005600:Fragile X Syndrome / Q000235:genetics*; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D007621:Karyotyping; D012729:Sex Chromosome Aberrations / Q000235:genetics*; D014960:X Chromosome