Researchers just recently discovered a way to quiet the extra chromosome, chromosome 21, which is responsible for Down syndrome, by adding a gene found in females. An international science journal, Nature, published a study this week that gave the details of how stem cells were used to mute the extra chromosome, as well as the paths this finding opens up for long-term treatments.
Although still a long ways from discovering a type of therapy that helps this chromosomal condition, scientists are enthused over the promises this discovery holds. For the first time, we now know that there is a way of manipulating the genetic defect in cells that causes Down syndrome. Down syndrome occurs when the 21st chromosome occurs three times in a cell rather than two like other chromosomes within a cell. The CDC reports that around 6,000 babies are born with Down syndrome every year.
Medical school scientists Jun Jiang and Jeanne Lawrence of the University of Massachusetts are two key individuals responsible for this amazing discovery. By taking what is called the XIST gene, a gene that is used to turn off one of the two X chromosomes in females, they found a way to disable chromosome 21. Down syndrome patients agreed to donate some stem cells from their skin that all contained the 21st chromosome. By applying the XIST gene to these cells, the chromosome that causes Down syndrome returned to normal. As Anthony Carter, PhD, of the National Institutes of Health states in an article in about this issue, this is interesting because Dr. Lawrence used a method that highlighted the fact stem cells, a natural part of humans, could help to reverse genes that have an irregular chromosome numbers.
This finding allows scientists to know more about the make-up of the causes and effects of cell diseases. This is important in advancing our knowledge of this condition, but more notably encountering ways to transform this knowledge into a therapeutic regiment. The next step is to test this in mice and see if the stem cells will correct their cell diseases in a way that might lead scientists one step closer to creating a type of therapy for these chromosomal defects.
