Fragile X syndrome is the most common inherited form of mental retardation, affecting approximately 1 in 3600 males and 1 in 4000-6000 females. Fragile X syndrome results from loss of expression of the Fragile X mental retardation protein (FMRP), the product of the FMR1 gene. Now, Drs. Robert and Jennifer Darnell and colleagues, from The Rockefeller University, report the uncovering of a new interaction between FMRP and messenger RNAs (mRNAs) containing a tertiary RNA structure termed a “kissing complex”. Their studies, published in the April 15th issue of Genes & Development, provide a new direction for efforts to understand how the loss of FMRP function leads to the complex behavioral and cognitive defects characteristic of Fragile X syndrome.
