Jesús Flórez
Professor of Pharmacology at the University of Cantabria and President of the Ibero-American Down21 Foundation
Regardless of the value of this study when it comes to understanding the increased frequency of hematological disorders in Down syndrome -particularly leukemias-, its results contribute significantly to deciphering the extraordinary variety in which certain comorbidities manifest in individuals with Down syndrome.
It is not enough that there is a triplication of genes specific to chromosome 21. These genes must be expressed in one way or another, and this largely depends on their topographical location within the genome, which is closely related to epigenetic factors linked to chromatin activity in a particular tissue and individual. The mere physical presence of an extra chromosome in the nucleus already constitutes, in itself, a deregulating factor in this relationship. The present study indicates this in relation to the intrinsic activity of hematopoietic cells in Down syndrome.
Additionally, the study confirms the importance of mitochondrial overexpression in Down syndrome, as evidenced by the increase in reactive oxygen species, which that act as damaging agents that facilitates the occurrence of DNA mutations capable of altering the division of hematopoietic cells.
Overall, the study broadens the molecular understanding underneath the pathology of any trisomy, in this case, trisomy 21 and its relation to hematological pathology.