Fragile X syndrome: Causes, symptoms and treatment.

After Down syndrome, it is the second most common genetic cause of intellectual disability.

Our genetic code carries the instructions necessary to shape and develop our bodies. We inherit much of what we are from our ancestors, although the expression or non-expression of some of these instructions will depend on the environment in which we live.

However, sometimes various genetic mutations occur that can result in the existence of a disorder in those who carry them. This is the case of Fragile X syndrome, the second most frequent cause of retardation.syndrome, the second most frequent cause of mental retardation due to genetic reasons.

Fragile X syndrome: Description and typical symptoms.

Fragile X syndrome or Martin-Bell syndrome is a genetic recessive a recessive genetic disorder linked to the X chromosome.. The symptoms produced by this syndrome can be observed in different areas.

The most notable are those related to cognition and behavior, although other symptoms such as typical morphological alterations or even metabolic problems may occur. Although it affects both men and women, as a general rule it is much more prevalent in the former, with more pronounced and severe symptoms.

Cognitive and behavioral symptoms

One of the most characteristic symptoms is the presence of intellectual disability.. In fact, together with Down syndrome, Fragile X syndrome is one of the most frequent genetic causes of mental retardation. This disability can be highly variable.

In the case of females, a level of intelligence on the borderline of intellectual disability is usually observed, with an IQ between 60 and 80. In males, however, in males, however, the level of disability is usually much higher.with an IQ usually between 35 and 45. In this case we would be dealing with a moderate disability, which would imply a slower development and delay in the main milestones such as speech, with difficulties in abstraction and the need for a certain level of supervision.

Another frequent aspect is the presence of a high level of hyperactivitypresenting motor agitation and impulsive behaviors. In some cases they may even self-injure. They usually also present concentration and attention maintenance difficulties.

It is also possible that they present typically autistic behaviorsThey may have severe difficulties in social interaction, phobia of contact with other people, mannerisms such as hand shaking and avoidance of eye contact.

Typical morphology

In terms of physical characteristics, one of the most common morphological features in individuals with Fragile X syndrome is that they have from birth a certain level of macrocephaly, possessing relatively large and elongated heads.possessing relatively large and elongated heads. Other common features are the presence of large eyebrows and ears, prominent jaw and forehead.

It is relatively common for them to have hyperlaxed joints, especially in the extremities, as well as hypotonia or muscle tone below what is to be expected.. Deviations of the spine are also frequent. In males, macroorchidism, or excessive testicular development, may also appear, especially after adolescence.

Medical complications

Apart from the types of characteristics that we have seen, people with fragile X syndrome may present alterations such as gastrointestinal problems or lower visual acuity. Unfortunately, many of them present cardiac alterations, having a greater possibility of suffering Heart murmurs. A high percentage, between 5 and 25%, also suffer from localized or generalized seizures or epileptic seizures.

Despite this, those with Martin-Bell syndrome can have a good quality of life. can have a good quality of lifeespecially if the diagnosis is made early and there is treatment and education that allow the effects of the syndrome to be limited.

Causes of this disorder

Fragile X syndrome is a genetic disorder linked to the sex X chromosome.

In people with Fragile X syndrome, the sex X chromosome undergoes a type of mutation which causes a specific series of nucleotides of the FMR1 gene, specifically the Cytosine-Guanine-Guanine (CGG) chain, to appear excessively repeated throughout the gene.

While subjects without this mutation may have between 45 and 55 repeats of this chain, a subject with Fragile X syndrome may have between 200 and 1300. This prevents the gene from being expressed correctly, so that it does not produce the FMRP protein because it is silenced.

The fact that the X chromosome is the one affected by the mutation is the main reason why the disorder is seen more often and with greater severity in males, but also in children. more often and with greater severity in males, The fact that only one copy of the X chromosome is. In females, possessing two copies of the X chromosome, the effects are less, and the symptoms may not even appear (although they can transmit it to their offspring).

Treatment of Martin-Bell syndrome

Fragile X syndrome currently has no cure at all. However, the symptoms caused by this disorder can be treated in a palliative way and in order to improve their quality of life, through a multidisciplinary approach that includes medical, psychological and educational aspects.

Some of the treatments that are used with people with this syndrome in order to improve their quality of life are speech therapy and different therapies. are speech therapy and different language therapies in order to improve their in order to improve their communication skills, as well as occupational therapy to help them integrate information from different sensory modalities.

Cognitive-behavioral programs and treatments can be used to help them establish basic and more complex behaviors. At the educational level, they need to have individualized plans that take into account their characteristics and difficulties. that take into account their characteristics and difficulties.

At the pharmacological level, SSRIs, anticonvulsants and different anxiolytics are used to reduce symptoms of anxiety, depression, obsessiveness, psychomotor agitation and seizures. Psychostimulant-type drugs are also occasionally used in cases where there is a in cases where there is a low level of activation, as well as atypical antipsychotics in those occasions when aggressive or self-destructive behavior tends to occur.