DNA scoring system improves kidney transplant matching
A new organ matching guide based on genetics could improve chances of long-term functionality and acceptance by donor's body. Bill Condie reports.
Doctors currently rely on several criteria including three main blood tests, cell surface tests and limited DNA tests to determine if a patient and a potential donor are a kidney match.
But the system is far from flawless. While transplant survival rates for patients with end stage renal failure are higher than for those treated with dialysis, 40% to 50% of kidney transplants still fail within 10 years.
Now scientists have come up with a comprehensive DNA scoring system using many genes to predict long-term success of transplantation. This new system is described in a study published in PLOS Computational Biology.
Current genetic tests detect differences in DNA sequences at just a few specific locations in the genomes of transplant recipients and their organ donor.
The fewer differences, the better the chance of long-term acceptance of the new organ.
But Laurent Mesnard and colleagues reasoned that a much larger scale collection of DNA data for a large number of genes would give a better indication.
And, after taking large samples from 53 pairs of kidney donors and recipients, he and his team developed a computational method that assigned a score to each pair based on mismatches in their DNA sequences.
They followed the progress of the patients following transplantation surgery over several years and found that the score significantly predicted the success of the transplanted kidneys.
“Future studies will be able to build on this new concept to confirm the initial observations,” study co-author Fabien Campagne said in a media release.
“They may lead to using this new concept in the clinic to optimise the matching of donor and recipients before transplantation.”
The researchers say that any process that improves the success rate of transplants will also take pressure off the shortage of kidneys for transplantation. A major contributor to shortages are patients who have to go back on the waiting list after an organ has failed.
The study was developed in a collaboration led by Weill Cornell Medicine, New York.