What are the genetic origins of intellectual disability? This complex and understudied question is central to Jamel Chelly’s research. Step by step, he is finding answers that could help people with certain neurodevelopmental disorders to live better with their condition.

Intellectual disability, signs of a "lost connection"

Neurological disorders have a diverse wide range of genetic origins. However, the cellular processes involved almost always concern the organisation of the cytoskeleton. This intracellular structure is involved, among other functions, in the growth of axons and dendrites, two main components of neurons.

In neurons, the dendrites receive nerve signals, the soma is the cell body that decodes these signals, and the axontransmits them. In other words, when the cytoskeleton is disrupted, it impacts the very connectivity of the brain. A better understanding of this dysfunction could pave the way to better treatment for certain mental disorders.

Decoding the genetics of intellectual disability

Jamel Chelly has been advancing our understanding of the genetic basis of neurodevelopmental disorders for nearly thirty years. His research work has revolutionised the approach to intellectual disability. He demonstrated that it was possible to study its molecular bases, despite the complexity of the problem. Noting that 30% of Duchenne muscular dystrophy patients suffer from an intellectual disability, Jamel Chelly began to focus his research in this field. After three years of tireless work, he managed to establish a genetic explanation. His work brings hope of improving the condition of people with intellectual disabilities.

The Foundation’s support

The researcher received support from the Fondation Bettencourt Schueller to explore a new field of study: the mechanisms of neuronal migration disorders and malformations of cortical development. His team has discovered numerous genes implicated in the development of intellectual disability, particularly on the X chromosome. Mutations in these genes cause intellectual disability in close to two in every thousand boys.

These findings have not only improved our understanding of the fundamental mechanisms of cognition, but have also facilitated the diagnosis and treatment of children. This work can be used to develop a rational approach to treatment (psychomotor therapy, language acquisition, education, etc.) tailored to each individual’s specific needs.

Jamel Chelly in a few words

As a young doctor, Jamel Chelly specialised in genetic medicine, while working with Axel Kahn and Jean-Claude Kaplan. Together with them, he discovered dystrophin, the protein responsible for the Duchenne and Becker muscular dystrophies. Recruited as researcher at the CNRS in 1988, he continued his research on dystrophin expression and developed his own method of RNA analysis.

He thereby discovered the process of "illegitimate" transcription. This very low-level expression of any gene in any tissue challenged the central tenets of genetics. In 1998, he managed to find a genetic explanation for certain mental disorders, through his research on Duchenne muscular dystrophy. He has continued this work ever since.

  • 1983 Doctor of Medicine, Sfax Faculty of Medicine (Tunisia)

  • 1987 PhD in Human Genetics, Paris Descartes University

  • 1988 CNRS Researcher, Inserm Molecular Genetics and Pathology Unit, Hôpital Cochin, Paris

  • 1991 Post-Doctoral Fellowship at the Laboratory of Professor Anthony Monaco, Weatherall Institute of Molecular Medicine, Oxford University (UK)

  • 1992 CNRS Bronze Medal

  • 1994 CNRS Research Director, Institut Cochin, Paris

  • 1995 Director of the laboratory for genetics and pathophysiology of neurodevelopmental and neuromuscular diseases, Paris

  • 1999 Liliane Bettencourt Prize for Life Science

Liliane Bettencourt Prize for Life Sciences

The Liliane Bettencourt Prize for Life Sciences rewards each year a researcher under the age of 45 for the excellence of their work and their remarkable contribution to their field of scientific research. This prize is awarded, depending on the year, to a researcher based in France or working in another European country. Thirty winners have been awarded since 1997. From 2023, prize rewards the laureate up to 100,000 euros.

All the award-winners