Who is Edith Heard, biologist specializing in epigenetics, CNRS gold medalist?

The 2024 CNRS gold medal, one of the most prestigious French scientific awards, distinguished biologist Edith Heard, specialist in epigenetics, whose work has shed light on the mechanisms of inactivation of the X chromosome and opened the way to medical perspectives.

The CNRS gold medal, one of the most prestigious French scientific awards, was awarded on Tuesday October 1 to the biologist, Edith Heard, a pioneer of epigenetics, the study of the mechanisms that modulate the expression of genes without changing the DNA sequence. Epigenetics helps explain, for example, why in each of us there are skin cells, hair, muscles or neurons that remain different throughout life, even though they carry exactly the same DNA.

“This discipline allows us to understand the development of life. But if we do not understand life, we have no hope of understanding diseases,” underlines Giacomo Cavalli, CNRS researcher at the Institute of Human Genetics. Beyond the specialization of cells in this or that tissue, research has also been able to show that certain epigenetic anomalies can be associated with cancers, psychological disorders or metabolic disorders such as obesity or diabetes, for example. If in this case we are not facing a genetic mutation, it seems that the expression of genes is still influenced by certain environmental factors such as chemical molecules, diet, stress or toxins, which can cause illness.

Edith Heard worked on these different phenomena. This 59-year-old researcher, professor at the Collège de France and director of the European molecular biology laboratory, is also the world specialist in X chromosome inactivation.

If you look back at your 4th grade program in college, you may remember that in women the sex chromosome pair is made up of two XX chromosomes while in men it is XY. One of the two X chromosomes is inactivated by the body, automatically, to balance genes. If the 2X genes were expressed twice, it would be toxic to the body. Edith Heard has succeeded in very precisely detailing the stages of the inactivation of one of the two