FRAXE expansion is not a common etiological factor among developmentally delayed males
- Hospital for Sick Children, Toronto (Canada)
Expansion of a (CGG){sub n} trinucleotide repeat unit at FRAXE, a newly defined fragile site distal to FRAXA, at Xq28, is reported to be associated with mild mental retardation. Three hundred developmentally delayed male patients referred for fragile X testing but negative for the FMR-1 gene trinucleotide expansion were screened for the FRAXE expansion. This group of patients had a wide range of intellectual or behavioral problems and included 19 patients who has low-level fragile site expression detected cytogenetically at Xq27-q28. None of the patients tested positive for the FRAXE expansion. These results suggest that FRAXE is not a common etiological factor among this group of patients. The data support the hypothesis that FRAXE is either very rare or a benign fragile site that is not associated with any clinical phenotype, similar to the FRAXF and FRA16A sites. 14 refs., 4 figs.
- OSTI ID:
- 91074
- Journal Information:
- American Journal of Human Genetics, Vol. 57, Issue 1; Other Information: PBD: Jul 1995
- Country of Publication:
- United States
- Language:
- English
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