Mutation analysis of fragile X syndrome by Southern blot, radioactive PCR, silver-stained polyacrylamide gel and DIG DNA
- CHA General Hospital, Seoul (Korea, Republic of); and others
Fragile X syndrome is the most common inherited form of mental retardation. In fragile X syndrome, the underlying mutation is caused by an expansion of the CTG triplet in the 5{prime} untranslated region of the FMR-1 gene located at Xq27.3 and diagnosed by methylation of the associated CpG island. This disorder becomes clinically manifested when the mutation is caused by an expansion of (CGG)n reaching a threshold of about 600bp (200 repeats). The number of inserted repeats increases through the generation. We have analyzed fragile X syndrome by 4 different methods: Southern blot, radioactive PCR, polyacrylamide gel and DIG DNA labeling/detection techniques. Southern blot and DIG DNA labeling/detection by double DNA digestion with EcoRI and EagI reveals both the presence of the mutation and the methylation status. Radioactive PCR and silver-stained polyacrylamide gel is a rapid and sensitive technique to define the unaffected carriers and NTMs, but it is difficult to amplify such a highly GC-rich sequence. Further testing in other fragile X patients is currently in progress.
- OSTI ID:
- 134756
- Report Number(s):
- CONF-941009--
- Journal Information:
- American Journal of Human Genetics, Journal Name: American Journal of Human Genetics Journal Issue: Suppl.3 Vol. 55; ISSN AJHGAG; ISSN 0002-9297
- Country of Publication:
- United States
- Language:
- English
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