INFORMATION ABOUT THE SRT
What is a syndrome?
The term syndrome derives from the Greek word "syndrome" which means simultaneity or concurrence.
In this case, referring to a genetic syndrome refers to a series of characteristics or alterations that occur simultaneously in a person, in their physiognomy, in their organs and in their development.
In turn, this series of simultaneous alterations occurs in multiplicity of people.
It should be clarified, however, that in general the carrier of a genetic syndrome does not present all of the characteristics described.
What is Rubinstein – Taybi syndrome (RTS)?
Rubinstein-Taybin syndrome carries several congenital abnormalities (conditions in which the baby is born). The main characteristics of people with this syndrome are usually broad thumbs and big toes, a small head size, typical facial features, arched palate, and varying degrees of generalized retardation.
What are the causes of Rubinstein-Taybi syndrome?
Known causes of the syndrome are microdeletions (loss of a piece of DNA) or mutations (changes in genetic information) in a gene. The genes so far identified as related to SRT are the CREBBP gene (or gene for the CBP-binding protein) in 60% of the cases, and the EP300 gene in 6% of the cases. The CREBBP gene is found on chromosome 16 and EP 300 on chromosome 22. At this time, it is unknown if there is another cause of this syndrome.
These changes in the gene generally occur spontaneously, this is called a “de novo” mutation and no direct relationship has been found between the syndrome and possible problems in pregnancy, or any other reason that suggests that parents they did something wrong or that a family member had the syndrome.
In other cases, it may be that there is already a history of the syndrome in the family and in this case there are possibilities of transmission.
What is the incidence of this syndrome?
It is difficult to know this data, since many cases are either misdiagnosed or not registered, but it could be around 1 case per 100,000 or 125,000 births, approximately. This syndrome affects both women and men, with equal frequency.
How is it diagnosed?
Diagnosis is usually made on the basis of certain typical characteristics: wide / angled thumbs and big toes, generalized or global developmental delay (growth, mental, etc.), behavioral problems, microcephaly, facial abnormalities (prominent forehead, fissures downward sloping eyelid, broad nasal bridge, convex nasal profile, arched palate, eversioned lower lip (outward), mild micrognathia (narrow chin), and minor abnormalities in the shape, position or rotation of the ears, the unusual grimace or smile, along with almost complete closing of the eyes when smiling.
Genetic tests are currently only capable of genetically confirming the diagnosis in approximately 65% of patients. In the future, it is expected to find new genes responsible for the rest of the cases.
Is it possible to have more than one child with the syndrome?
If a couple in which neither partner is affected by RTS has had a child with this syndrome, the chance of having another child with the same syndrome again is approximately 0.1%. However, if a person with the syndrome has a child, the risk of recurrence in this case is about 50%.