National / Science & Health

Gene abnormalities occur in iPS cell conversion process

JIJI

Cancer-related genetic abnormalities have reportedly occurred during the process of transforming induced pluripotent stem (iPS) cells supplied by Kyoto University into intended cell types at recipient research institutes.

None of the affected iPS cells, which are used for regenerative medicine, have been used for transplantation, according to sources.

It is known that genetic abnormalities could occur when cells are cultured or transformed.

Kyoto University’s Center for iPS Cell Research and Application, or CiRA, is stockpiling iPS cells that were produced based on cells taken from healthy people. CiRA started to supply them to research institutes and businesses in 2015.

Problems, including cancer-related genetic abnormalities, have been confirmed in at least some of cells created from two of the 27 types of iPS cells that CiRA has provided so far, according to the university.

The abnormalities are believed to have happened during the cell creation processes at the recipient institutes, as the university confirmed no abnormality in the iPS cells through an analysis of all of their genomic information before their shipments.

While noting that the frequency of such abnormalities is not high, a Kyoto University official said the school is considering releasing information about the abnormalities that occurred.

Yoshimi Yashiro, a regenerative medicine expert at Kanagawa University of Human Services, said there will be “no big risk” because cells are checked for abnormalities before transplantation.

“Kyoto University and researchers concerned need to disclose information on the frequency of abnormalities and the processes that led to the problems, and consider measures in response to the issues,” Yashiro said.