One hundred years ago, on June 13, Jérôme Lejeune was born. What remains of that legacy that the Foundation continues to embrace today? “A savoir-faire, a savoir-dire, a savoir-être”, knowing how to do, knowing how to speak, and knowing how to be.
Generally speaking, what is remembered about Jérôme Lejeune is his “knowing how to do”.
As the discoverer of trisomy 21 in 1958, he was a world-renowned authority and a key figure in the development of cytogenetics, that is, the study of chromosomes and diseases related to chromosomal abnormalities, particularly those caused by changes in chromosome number. He was also a physician who cared for patients with intellectual disabilities.
Because trisomy has a constitutional origin—it occurs at the time the embryo is formed—Jérôme Lejeune understood human life in its entirety, from its beginning at fertilization, and not merely from birth. This explains his early passion for deeply innovative scientific research, which made him one of the first to anticipate the beginnings of gene therapy.
At the time, some still believed that so-called “mongolism” could be caused by a sexually transmitted disease in the mother or that it was hereditary. This gives an idea of how little was known and of how Lejeune, using new scientific tools, was able to sustain hope for a cure, becoming one of the fathers of modern genetics.
Perhaps it has been forgotten, but Professor Lejeune also had a “knowing how to speak”, because above all, he was a man of his word.
He was the first physician capable of telling a mother that her child with trisomy was not an aggressor, was not a child born of sin, but a child born of love, and that the child could be happy, just as his or her parents could be.
During the nearly thirty years he spent at the Necker-Enfants Malades Hospital, he restored dignity and pride to thousands of families, who remain grateful to him to this day and continue to bear witness to his impact.
There was a time when scientific errors that stigmatized the “imperfect” were no longer being propagated, and when society had not yet decided to subject them to a silent form of eugenics through prenatal diagnosis and euthanasia. He welcomed, with naturalness and compassion, women who were afraid of raising a child with a disability; he received them, did not judge them, but instead reassured them.
Today, perhaps, Jérôme Lejeune could even face legal action for doing so
“The development of biological techniques will be dazzling, but will man be struck down by them?” – Jérôme Lejeune
Most important of all was Jérôme Lejeune’s “knowing how to be”, which surpasses everything that came before.
The extraordinary coherence of his life led him to show, with serenity, that it is possible to hold together rational rigor and love of neighbor, the advancement of knowledge and respect for human life, medical tradition and the need to innovate.
His freedom of spirit was complete because, as he himself said, “I did not work for myself”. He did not strive for money or honors, but solely for the good of humanity.
He lamented that human beings had decided to put themselves in God’s place, defining for themselves what is right and what is wrong, with all the risks that this entails. Preventing the drift toward a humanity that destroys life: this is the message he left, not only to his patients or to the medical profession, but to the entire world.
Each generation is called to take up that torch and carry it forward, in order to remain truly human.
Jean-Marie Le Méné, President of the Jérôme Lejeune International Group.
If you would like to learn more about the life of Jérôme Lejeune and the enduring relevance of his legacy—that savoir-faire, savoir-dire, and savoir-être that continue to inspire the Foundation’s mission today—we invite you to take the free Jérôme Lejeune Centennial Course.
This free educational program offers a journey through Lejeune’s life, work, and legacy through lectures, testimonies, and encounters with international voices: physicians, geneticists, professors, legal experts, family members, colleagues who worked alongside him, and bioethics experts who continue his legacy today in academic, clinical, and human settings.
Each testimony is presented in the speaker’s original language, with English subtitles, preserving the richness and authenticity of each voice. This course invites you to discover not only the milestones of his scientific career, but also his medical vocation, his humanity, his faith, and the moral courage that made Jérôme Lejeune a truly exceptional figure.
