Severe combined immune deficiency

  • Thread starter Monique
  • Start date
In summary, two out of fifteen SCID patients cured by retroviral gene therapy developed leukemia, suggesting that gene therapy may not be as safe as previously thought. It is unknown how the virus attached itself to the genome, but it might be possible to target a virus to a specific "junk region" of the genome.
  • #1
Monique
Staff Emeritus
Science Advisor
Gold Member
4,219
67
I thought it was interesting to note that out of 15 SCID (severe combined immune deficiency) patients cured by retroviral gene therapy, 2 developed leukemia.

This as a direct integration of the virus into a pro-oncogene, the interesting thing is that both patients had an insert in the same gene! (LMO-2)

This poses questions on the safety of gene therapy. Ofcourse, not all virusses integrate themselves into the genome (like adeno, or adeno-associated virusses) but those other ones bring severe immunological risks with them..


I wonder, wouldn't it be possible to target a virus to a specific 'junk region' of the genome? I am not sure how virusses integrate themselves, they probably depend on regions with less dense histone packing..
 
Biology news on Phys.org
  • #2
Derek Lowe's article

http://www.corante.com/pipeline/ [Broken] had an article about this a month or so ago - you might have to look in his archives for it. Basically what he said is that the attachment links are not randomly distributed in the chromosome, and that the probablility that your vector will attach near a leukemia site cannot be estimated by uniform distribution, which is what the experimentalists did. How the attachment points really are distributed, and why they seem to nestle close to leukemia sites is material for future research.
 
Last edited by a moderator:
  • #3
I looked in the archives, but didn't find anything.

So how did these researchers know it is not uniformly distributed and is not random? I agree that lightning striking the same spot twice is suspicious, but since these are specific blood cells which will require a specific growth hormone, it might not be that striking that cells with this particular mutation have a growth advantage.

How did they find this gene in particular to be faulty anyway? Maybe there are a dozen more of the same genes defective in the same patients?
 
  • #4
I'll see if I can find the paper/
 

1. What is severe combined immune deficiency (SCID)?

Severe combined immune deficiency, also known as "bubble boy disease", is a rare genetic disorder that affects the immune system. It is characterized by a severe deficiency in both T cells and B cells, making individuals highly susceptible to infections.

2. What are the symptoms of SCID?

The symptoms of SCID can vary depending on the severity of the condition, but common symptoms include recurrent or persistent infections, failure to thrive, and chronic diarrhea. Babies with SCID may also have a rash, fever, and cough.

3. How is SCID diagnosed?

SCID is typically diagnosed through a blood test that measures the number of T cells and B cells in the body. A genetic test may also be performed to identify the specific gene mutation causing SCID. In some cases, a newborn screening test can detect SCID before symptoms appear.

4. Is there a cure for SCID?

Currently, there is no cure for SCID. However, there are treatments available that can help manage the symptoms and improve the quality of life for those with SCID. These treatments include bone marrow or stem cell transplants, gene therapy, and medications to prevent and treat infections.

5. Can SCID be prevented?

SCID is a genetic disorder and cannot be prevented. However, early detection through newborn screening and prompt treatment can help improve outcomes for individuals with SCID. It is also recommended that individuals with SCID avoid exposure to infections and receive all necessary vaccinations to prevent illness.

Similar threads

  • Biology and Medical
Replies
19
Views
8K
  • Biology and Medical
Replies
2
Views
7K
  • Biology and Medical
Replies
2
Views
11K
Back
Top