FMR1 fragile

Gibson, T. J., Rice, P. M., Thompson, J. D., and Heringa, J. (1993). KH domains within the FMR1 sequence suggest that Fragile-X syndrome stems from a defect in RNA metabolism. Trends Biochem. Sci. 18, 331-333. 

Figure 1-5. Diagram of the fragile X mental retardation (FAIR ) gene with restriction map and FMR1 probes used for diagnostic Southern blots. The circle indicates the CpG island, and the box represents the first exon. The dark region shows the location of triplet repeats.

Fragile X families exhibit two types of FMR1 gene mutation. The repeat expansion of more than 230 copies with subsequent methylation of the CpG island is referred to as a full mutation. All males and about half of the females who carry full mutations have mental retardation. Mosaic males with full mutations are almost always affected to the same extent as fully affected males, while mosaic females vary in... 

Fragile X syndrome Xq27.3 CGG Maternal 6-50 Premutation 50-230 Full mutation 230-2000 FMR1... 

Siomi H, Siomi MC, Nussbaum RL, et al. The protein product of the fragile X gene, FMR1, has... 

Fig. 6. Hypothesis model representing the switching off and on of the FMR1 gene in X-fragile syndrome as a function of DNA structural dynamics...

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