Fragile X Syndrome – Causes and Symptoms of Fragile X Syndrome
Fragile X syndrome is a genetic disorder and is a common form of subnormal intellectual developmental . The disorder leads to severe physical disabilities in the affected person. It is a condition that is caused due to a gene defect called FMR1. It is also called as Martin-Bell syndrome.
The condition affects both men and women equally. On an average, it was found that 1 of 3600 males and 1 of 4000 females are affected with this disorder. The degree of mutation of gene differs and hence the syndrome’s effect may vary from person to person.
Causes of Fragile X Syndrome
The main cause of Fragile X syndrome is a minute change in a single gene, known as Fragile X Mental Retardation 1 (FMR1) gene. FMR1 gene is present on X chromosome.
A specific gene makes a specific protein to perform a specific job. Proteins are building blocks of the body and make up the organs and tissue structures. A particular information is stored in each gene to make one protein. If a gene does not contain any information or the information is changed, it will be unable to form a protein.
In the same way, a mutation in FMR1 gene makes it unable to produce the information required for Fragile X Mental Retardation Protein (FMRP). A person with normal amounts of FMR protein has no or mild symptoms, likewise a person with no amount of FMR protein has severe disease symptoms.
The affected men with fragile X gene cannot pass it on to their sons as they can give only Y chromosome to male child. But they can pass the defective gene to their daughters since female child receives X chromosome from father. Women can pass their defective gene to both sons and daughters as they carry two X chromosomes.
Symptoms of Fragile X Syndrome
The common signs and symptoms of Fragile X Syndrome are as follows:
Sensory – Certain sensations such as loud noises, feelings and bright light make the affected person bothered. They don’t like to bo touched and face trouble in making eye contact with the other person.
Speech and language – Affected person may stammer and face a difficulty in speaking. The other person may find difficult in hearing to the tone of affected person.
Social and emotional – Affected person may be anxious or afraid in various situations. Especially, males have trouble in paying attention and are aggressive. Girls are usually shy.
Physical – Long ears, jaws and faces, loose and flexible joints, flat feet are the physical symptoms.
Intelligence and learning – Intellectual and learning disabilities.