October 12, 2015

expert reaction to study using CRISPR to produce pig organs suitable for xenotransplantation into humans

Publishing in the journal Science, a research group has reported their use of the CRISPR-Cas9 system to modify genes in pigs with the aim of improving acceptance of organs transplanted into humans.

Professor James Murray, Department of Animal Science, University of California, Davis CA, said:

“This is an excellent demonstration of the power of the CRISPR/Cas 9 system and one that I have been expecting. The presence of PERVs in pig lines has been of great concern, and a limiting factor, in the application of xenotransplantation. The CRISPR system presented a methodology to remove PERVs and this work demonstrates that it can be effectively done. This work also provides a new on simultaneous edits by the disruption of all 62 PERVs inserts by one treatment. This now needs to be done in cells engineered for xenotransplantation and cloned animals derived to establish a PERVs free line of pigs.”

Prof. Bruce Whitelaw, Professor of Animal Biotechnology, Roslin Institute, University of Edinburgh, said:

“The report from the Church group continues to raise the profile of genome editing technology. Their study, by simultaneously editing many genetic loci, is a dramatic advance on previous reports where on a few target loci were edited. This study experimentally addresses a challenge for xenotransplantation and, if replicated in animals, could be another step towards this biomedical goal. Perhaps more importantly, although in the report by Yuhan Yang multiple copies of the same DNA sequence were edited, their achievement suggests that it may well be possible to target multiple different sequences.”

Dr Sarah Chan, Chancellor’s Fellow, Usher Institute for Population Health Sciences and Informatics, University of Edinburgh, and member of the Hinxton group, said:

“This work is of particular scientific interest as an example of effective multiplex gene editing (altering multiple genetic sites at once) on a much larger scale than previously reported. Of course, there is still a long way to go to overcome other problems associated with pig xenotransplants, notably immune compatibility, and even once the scientific and safety issues have been addressed, we should be mindful of the possible cultural concerns and societal impacts associated with more widespread use of pig organs for human transplantation. Nonetheless, the results of the study are valuable both as a proof of principle and a potential step towards therapeutic advances in this area of much-needed research. Moreover, by demonstrating that genome editing can be used to remove unwanted genetic elements that could pose barriers to treatment, the study illustrates the broad applicability of these techniques for a range of potentially therapeutically useful purposes beyond human genetic modification.”

“Genome-wide inactivation of porcine endogenous retroviruses (PERVs)” by Luhan Yang et al. published in Science.

All our previous output on this subject can be seen at this weblink: http://www.sciencemediacentre.org/tag/genome-editing/

The SMC produced a Factsheet on genome editing which is available here: http://www.sciencemediacentre.org/genome-editing/

Declared interests

Prof. Bruce Whitelaw: “On SAB of Recombinetics Inc and Immunogenes AG.”

Dr Sarah Chan: “I have no competing interests in regard to this matter”