X-chromosome linked diseases Fragile X syndrome The fragile x-syndrome is caused by a change in the promoter area of a gene called FmrP (fragile x mental retardation 1)protein. The coding area for this gene is located on the X-chromosome. FMRP is mainly expressed in the brains and testicles One current research study revealed that certain cell processes in brain cells use to communicate with one another occur in excess in mice that have little or no FMRP, that is, the brain cells may communicate too much or may communicate inappropriately. Researchers believe that FMRP may regulate the amount of communication between cells and keep it under control. Scientists are hopeful that they can identify a similar function for FMRP in humans The number of carrier women, of all races, is thought to be as high as 1: 259 This syndrome strikes males about twice as often as females. About 1: 2000 males are affected and about 1: 4000 females are affectedFragile X syndrome The fragile x-syndrome is caused by a change in the promoter area of a gene called FMRP (fragile X mental retardation 1) protein . The coding area for this gene is located on the x-chromosome . FMRP is mainly expressed in the brains and testicles. One current research study revealed that certain cell processes in brain cells use to communicate with one another occur in excess in mice that have little or no FMRP; that is, the brain cells may communicate too much or may communicate inappropriately. Researchers believe that FMRP may regulate the amount of communication between cells and keep it under control. Scientists are hopeful that they can identify a similar function for FMRP in humans. X-chromosome linked diseases The number of carrier women, of all races, is thought to be as high as 1:259. This syndrome strikes males about twice as often as females. About 1:2000 males are affected and about 1:4000 females are affected