Would it be possible to improve the condition of someone with Down's Syndrome through gene therapy?

Question

Given that, before too long all of the cells in our body would be replaced by new ones, why wouldn't it be possible to use gene therapy to improve the condition of someone with Down's Syndrome?

Answer 1

Since Down's syndrome is the presence of a third copy of 1 chromosome in every cell, any treatment would have to somehow negate 1 of those 3 chromosomes in every cell in the body. You would need some sort of treatment that could target just 1 and it would absolutely have to leave the other 2.

There is a technique used in molecular biology known as gene silencing. However, I am 99% certain that this technique could not be used to selective target 1 of 3 alleles, and 100% certain that it isn't possible for it to be done for every gene on an entire chromosome.

Also, I believe that you are mistaken about the lifespan of cells in the human body. Some, such as skin cell, divide with some frequency, others such as liver cells divide more slowly while others such as nerve cells divide quite infrequently.

Answer 2

Down's Syndrome is also called trisomy 21 because instead of having 2 copies of the 21st chromosome they have 3. This results in the syndrome as we know it. Gene therapy, where it can be applied can only correct one flawed gene, not an entire chromosome, much less an extra copy of said chromosome.

Answer 3

Down's Syndrome is a genetic condition where the person's genes are incorrectly formed. So it is possible to teat them with gene therapy; provided you find a reliable way to do it. The problem with those suffering Down's Syndrome is that since their genes are flawed those flawed genes continue to reproduce themselves in the flawed manner. To correct Down's Syndrome the genetic code in every single gene must be checked and rewritten.

Answer 4

No. The replacement cells will have the same genetic structure as their antecedents; gene therapy does not replace the structure of existing cells.

Answer 5

An entire chromasome is missing from their nuclei, the only way to effectively help genetically is by installing new artificially generated chromasomes into all the original stem cells, but it could only be ethical if you used the parents DNA. I do not believe this has been sucessful before in trials.