Fragile X syndrome, also termed Martin-Bell syndrome or marker X syndrome, is the most common cause of inherited mental retardation. Fragile X syndrome has been found in all major ethnic groups and races, and is caused by an abnormality (mutation) in the FMR1 gene. FMR1 is a gene located . Fragile X syndrome is caused by the expansion or lengthening of the FMR1 gene on the X chromosome, known as a gene mutation. The X chromosome is one.

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Genetic X-linked dominant [1].

The fragile X syndrome affects about 1 in 4, males and 1 in 6, to 8, females in the USA; that is, it affects about twice as many males as it does females.

Archived from the original on 12 October Merck Research Laboratories; In contrast, female offspring whose fathers have a premutation always s it and thus grandchildren of males with the premutation are at risk to have fragile X syndrome. This means that children born with Fragile X frequently appear in families with no previous history of intellectual disability.

Some current clinical trials also are posted on the following page on the NORD website: New medications are likely to become available to treat affected individual and the specialty clinics can assist parents with current information.

Chromosomes, which are present in the nucleus of human cells, carry the genetic information for each individual. Am J Ment Defic. Females have two X chromosomes and males have one X and one Y.

Occasionally, in some individuals with repeats there will be some minor instability such that these individuals will have several more or less repeats than their parents. Standard Therapies Treatment There are many treatments for fragile X syndrome that can improve the lives of affected individuals and their families. Females with the abnormal gene may be affected by this disorder.


What is Fragile X Syndrome? • Fragile X Research – FRAXA Research Foundation

Am J Intellect Dev Disabil. From Genetics to Targeted Treatment. Some girls have no signs at all. Pediatrics ; Suppl 3: Surgery or patching are usually necessary to treat strabismus if diagnosed early. Information on current clinical trials is posted on www. Chromosomes are further sub-divided into many bands that are numbered.

Speech may be cluttered or nervous. After puberty, testes will be smaller than normal. The fragile X premutation: Therapies Psychotropic medication antipsychotics Aripiprazole Risperidone.

What is Fragile X syndrome?

Noticeable by age 2 [1]. Diseases of unstable repeat expansion: Years Published,,, Autism-related topics Fictional characters Schools. Public health literature review of fragile X syndrome. However, in a premutation individual, CGG length is only significantly correlated with the central executive, not with frajjl phonological memory or visual—spatial memory.

What causes Fragile X Syndrome

Transitions from one location to another can be difficult for children with FXS. Developmental delay is present in Renpenning syndrome early with males learning to walk at age 2 — 3 years and able to say simple words at age 3 — 4 years.

The Johns Hopkins University. Handbook of neurodevelopmental and genetic disorders in children. Machado—Joseph disease Aneurysmal bone cyst Multiple familial trichoepithelioma 1.

Watch the digital animation below for a pictorial view of how the genetics of Fragile X work. Comparisons may be useful for a differential diagnosis: FMRP is involved in making connections between neurons nerve cells in the brain. Supportive careearly interventions [2]. It appears that individuals with FXS are interested in social interaction and display greater empathy than groups with other causes of intellectual disability, but display anxiety and withdrawal when placed in unfamiliar situations with unfamiliar people.


The subsequent abnormalities in the formation and function of synapses and development of neural circuits result in impaired neuroplasticityan frajip part of memory and learning. With educational efforts, therapy, and support, all individuals with fragile X syndrome can make progress. Daughters born to male carriers will inherit their fathers affected X chromosome and they will also be carriers.

The physical features in affected males are variable and may not be obvious until puberty. Dentatorubral-pallidoluysian atrophy Huntington’s disease Kennedy disease Spinocerebellar ataxia 1, 2, 3, 6, 7, 17 Machado-Joseph disease. Learn More Related Issues Genetics.

J Neurodev Disord ; 9: Phonological memory or verbal working memory deteriorates with age in frajill, while visual-spatial memory is not found to be directly related to age. Some drugs, originally developed to treat other disorders, were shown to be effective in treating symptoms of fragile X syndrome in the animal models but when used on human subjects appeared to be less effective.

Unlike many genetic diseases, it may not be apparent that a person has Fragile X. Cognitive behavior therapy social skills training Discrete trial training Lovaas Early start denver model Pivotal response treatment Schoolwide positive behavior support. In the meantime, appropriate education and therapies may help and medications are available that farjil symptoms.

Models and mechanisms of repeat expansion disorders: Current pharmacological treatment centers on managing problem behaviors and psychiatric symptoms associated with FXS.