Mutation spectra in fragile X syndrome induced by deletions of CGG*CCG repeats.

摘要: The fragile X syndrome results from expansions as well deletions of the repeating CGG·CCG DNA sequence in 5′-untranslated region FMR1 gene on chromosome. relative frequency disease cases promoted by these two types mutations cannot be ascertained at present because routine clinical assay monitors only expansions. At least 30 articles have been reviewed that document involvement part or all repeats along with varying extents flanking regions very small including single base pair changes. Studies deletion mutants tracts Escherichia coli plasmids revealed a similar spectrum mutagenic products. triplet repeat tract non-B conformation is mutagen, not per se right-handed B helix. Hence, molecular investigations simple model organism may generate useful initial information toward therapeutic strategies for this disease.