Research Report ‘Can new gene therapies result in unintended germline modification? Unveiling the frontiers: current insights and limits of testing’

The Central Committee on Research Involving Human Subjects (@CCMO) and the Netherlands Commission on Genetic Modification (COGEM) commissioned a study into the risk of unintended germline modification, with a particular focus on new forms of gene therapy. The study was conducted by Sciensano and Perseus BV.

Germline modification involves changes to germ cells, which can lead to (adverse) consequences for offspring. Modifying germ cells is not permitted. Therefore, it is  of great importance to know whether unintended germline modification can occur as a “side effect” of gene therapy, and what consequences this could have for treated individuals who wish to have children in the future.

The report discusses the various forms of gene therapy currently under development and provides an update on the available data regarding the distribution of gene therapy throughout the body (biodistribution) and the likelihood that unintended germline modification may occur. It also lists the relevant gene therapy guidelines from, among others, the FDA and the EMA.

The main conclusions of the report are that the occurrence of unintended germline modification has very rarely been the subject of research in the past. However, the limited available information does not indicate that gene therapy leads to changes in germ cells and that the genetic modifications are passed on to offspring.