Fragile X syndrome is a genetic chromosome abnormalities disorder that requires a medical diagnosis.
Fragile X syndrome is a Genetic condition that causes mild to severe intellectual disability in both male and females. The syndrome also causes behavioral and learning challenges and various physical characteristics 
Some of the symptoms of Fragile X syndrome include delays in talking large ears, speech impairment, anxiety, double jointed, enlarged head, enlarged testicles, flat feet, lazy eye, long thin face, prominent jaw, scoliosis, single line on palm, sleep disorder, sunken chest, or tremor some people have seizures. Physical features would include large ears, a long face, a prominent jaw and forehead and flat feet. Some of the behavioral features are aggression, hyperactivity, impulsivity, nonsense word repetition, repetitive movements, self-harm or persistent repetition of words or actions. The Developmental features are learning disability or speech delay in the child. The Muscular features would be flaccid muscles or problems with coordination  

Fragile X syndrome is caused by the expansion or “lengthening” of the FMR1 gene on the X chromosome which is known as a gene mutation. The X chromosome is one of two sex chromosomes. When the gene lengthens it causes the switch off of a production of a protein that is involved in the brains development and other functions. 
 Treatments that can be used to treat the learning disability are Behaviour Therapy, Medications like Sedative, Muscle Relaxant, Antipsychotic, Cognition-enhancing medication and Vitamin and specialists like Paediatrician, Medical Geneticist, Speech therapist, Occupational Therapist, Clinical Psychologist, Physiotherapist and Neurologist 

https://fragilex.org.au/what-is-fragile-x/
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