Fragile X syndrome is a genetic condition that leads to a variety of developmental delays and cognitive problems, such as learning disabilities, intellectual disabilities, anxiety, hyperactivity and impulsive behavior, according to Genetics Home Reference. Fragile X syndrome affects around one in 4,000 males and one in 8,000 females.
Individuals with fragile X syndrome often have problems with social interaction and communication, states Genetics Home Reference. They may also experience delayed speech and language development, seizures and attention deficit disorder. Individuals with fragile X syndrome often have common physical characteristics, such as a long, narrow face, large ears, a prominent jaw and forehead, flat feet and extremely flexible fingers. Males also typically experience enlarged testicles after puberty.
Fragile X syndrome occurs as a result of changes in the fragile X mental retardation 1, or FMR1, gene, explains the Centers for Disease Control and Prevention. The FMR1 gene makes a protein called fragile X mental retardation protein, or FMRP, which is required for normal brain development. In individuals with fragile X syndrome, changes in the FMR1 gene prevent it from making this protein. Diagnosis of fragile X syndrome occurs through use of a special DNA blood test. Fragile X syndrome does not have a cure, but treatment, such as therapy and medications, can improve an affected individual's quality of life.