San Raffaele Telethon Institute for Gene Therapy

Safety of gene therapy and insertional mutagenesis


Group Leader

Eugenio Montini


Gene therapy (GT) applications in the recent years have advanced close to realizing their full potential. GT however is still in its infancy and a significantly uncharted territory and unique challenges remain to be addressed. Notably, the lack of entirely neutral gene delivery or editing platforms and consistent readouts for safety monitoring predictive for the long-term impact of these therapies represent an outstanding issue for the whole GT field.

The ‘Safety of gene therapy and insertional mutagenesis’ research unit is committed to overcome these challenges by unraveling the basic mechanisms governing genotoxicity in gene therapy and improve the safety of GT applications by modifying the current vector designs to deliver transgenes efficiently without impacting the expression or mRNA structure of genes nearby vector integration sites and to discover novel biomarkers predictive of the safety of GT treatments, outcome of the therapy and disease burden.

To reach these goals we have developed sensitive genetic mouse models for testing the genotoxic potential of different vector types and backbone designs, state of the art high throughput retrieval and next generation sequencing of vector insertion sites, methods to study the long-range interactions between vector and cellular genome and a solid bioinformatics and statistical framework to analyze and integrate genomic and phenotypic data.

Research activity

Our activity is organized in three main areas:

  1. Improving the safety of gene transfer. We use mouse models and powerful molecular technologies (4C, HiC, ChIP-seq, RNA-seq) to unravel the basic mechanisms governing genotoxicity and to compare the impact of integration of vectors with different designs and/or containing genetic elements to potentially improve their safety. We aim to capitalize on the gained knowledge to devise and validate novel vector designs with improved safety profile to be adopted as “gold standard” in future ex vivo and in vivo GT applications.
  2. Characterization of the safety and dynamics of clonal reconstitution in ex vivo GT.  We aim to understand several basic aspects of human hematopoiesis by dissecting the clonal dynamics of hematopoietic reconstitution in hematopoietic stem cell-GT patients and unveil factors that impact on the outcomes of the therapy in terms safety and efficacy under different genetic, clinical, and environmental conditions.
  3. Uncovering the effects of insertional mutagenesis beyond cancer. We aim to identify markers for the detection of cells with risky cancer promoting insertions (or mutations), understand their impact on the surrounding microenvironment and at the whole organismal level. We also aim to devise methods that will allow to eliminate specifically cell harboring genotoxic insertions in vivo.