What is Trisomy 8 Syndrome

Trisomy 8

1 definition

The Trisomy 8 is the triple presence of chromosome 8 and is a chromosome aberration. It occurs sporadically and, with 120 known cases, is considered rare. Most often there is a mosaic trisomy 8 in which only some of the cells have the additional chromosome. Free trisomy 8, in which the additional chromosome 8 can be detected in all body cells, is less common.

2 background

Trisomy 8 is usually congenital, but it can also occur acquired in certain cell lines. A trisomy of 8 clonal hematopoietic stem cells, for example, is a possible change in the karyotype in myelodysplastic syndrome (MDS).

3 prenatal diagnostics

The following abnormalities are often associated with trisomy 8, which can be detected in prenatal ultrasound:

To date, a definitive diagnosis can only be made by examining the chromosomes themselves. Amniocentesis or chorionic villus sampling are often used for prenatal diagnosis. In the case of a chorionic villus sampling, it must be borne in mind that a mosaic trisomy 8 can also occur in a placental area, i.e. the baby does not have a fetal mosaic.

4 Postnatal abnormalities

The clinical picture is variable, especially with mosaic trisomy 8. People are also known for whom there are hardly any abnormalities. The degree of severity is decisive for the prognosis of the physical as well as the mental development. If the proportion of trisomeric than disomeric cells is significantly lower, normal development is possible.

5 therapy

There is no cure for trisomy 8, but symptoms can be treated.