Fragile X syndrome is a genetic disease that occurs due to a mutation in the X chromosome, leading to the occurrence of several repetitions of the CGG sequence. Because they only have an X chromosome, boys are more affected by this syndrome, presenting more characteristic signs, such as elongated face, large ears and flap, and behavioral traits similar to that of autism. This mutation can also happen in girls, however the signs and symptoms are much milder, because as they have two X chromosomes, the normal chromosome compensates for the defect of the other.
The diagnosis of fragile X syndrome is difficult, since most of the symptoms are non-specific, but if there is a family history, it is important to perform a genetic counseling so that the chances of the syndrome are verified. Understand what genetic counseling is and how it is done.
Signs and Symptoms of Fragile X Syndrome
Fragile X syndrome is highly characterized by behavioral disorders and intellectual impairment, especially in boys, and there may be difficulty in learning and speaking. In addition, they are characteristic symptoms of fragile X syndrome:
- Elongated face;
- Large ears;
- Outgoing chin;
- Low muscle tone;
- Connective tissue involvement;
- Flat feet;
- High palate;
- Mitral valve prolapse;
- Single palmar nail;
- Strabismus or myopia;
- Scoliosis;
- Habit of biting hands;
- Otitis recurrent.
Most of the characteristics related to the syndrome are only noticed from adolescence. In boys, the occurrence of enlarged testes is common in adolescence, while females may have problems with fertility and ovarian failure.
How is the diagnosis made?
The diagnosis of fragile X syndrome can be done by molecular and chromosomal tests to identify the mutation, the number of CGG sequences and the characteristics of the chromosome. These tests can be done with a blood sample, saliva, hair or amniotic fluid.
How is the treatment done?
Treatment for Fragile X syndrome is done through behavioral therapy, physical therapy and, if necessary, surgery for physical changes.
People with a history of fragile X syndrome in the family should seek genetic counseling to determine the likelihood of having children with the disease. Men have the XY karyotype, and if they are affected they can transmit it only to their daughters, never to their children since the gene received by the boys is the Y, and it does not show any changes related to the disease.