The centennial of Jérôme Lejeune’s birth was celebrated this week at the Colegio Mayor Roncalli in Madrid, with an event that brought together family members, doctors, and thinkers to honor the French geneticist, who discovered the chromosomal cause of Down syndrome and was one of the 20th century’s greatest defenders of human dignity.
During the ceremony, Elena Postigo, president of the Jérôme Lejeune International Chair in Bioethics, read a letter from the current president of the Pontifical Academy for Life, Monsignor Renzo Pegoraro, noting that Lejeune was the first president of that very institution and that «we are called upon to remember his life and his legacy.”.
He also pointed out that, in his view, “the central point is that human dignity is indisputable, and that dignity begins at the start of life, at the moment of conception.” He added that “a person’s dignity does not depend on their abilities, wealth, or the role they play,” but rather is “a gift that precedes and transcends them.”.
The event consisted of a conversation between Jean-Marie Le Méné, Lejeune’s son-in-law and president of the Jérôme Lejeune Foundation in France, and the writer and philosopher Fabrice Hadjadj, father of a son with Down syndrome, moderated by José Martín Aguado, also the father of a son with trisomy 21. Le Méné focused on debunking the image that, as he said, circulates about Lejeune in certain circles: that of a rigid scientist opposed to progress.
In light of this, he has paid tribute to a man whose defining trait was “perpetual wonder.” He also summarized the medical ethics he observed in his father-in-law with an idea he has repeated almost like a motto: the doctor’s role is to care for the patient, not to hasten their death, but also to always prevent them from suffering. He also shared a personal memory: the death of a sister in his childhood when she was just four months old, from a condition that today would be easily treated: “It has haunted me personally my whole life.”.
Hadjadj, for his part, offered a more philosophical reflection, contrasting the figure of the superman—doomed to become obsolete by his own logic of technical advancement—with that of a child with Down syndrome: “The problem with the superman is that he is always caught up in competition, whereas the child possesses something more—not primitive, but primordial,” with a simplicity that “broadens our hearts, our historical consciousness, and our relationship with nature.” And he posed the question that, in his view, sums up the true challenge: “Who are the weak in this case? We are, because each of us has our own weakness.”.
Course on Lejeune
The centennial also provided an opportunity to present a course that explores the life of Lejeune from a variety of perspectives. Pablo Siegrist, executive director of the Jérôme Lejeune Foundation in Spain, presented the course content, which features, among others, his children Karin and Thomas Lejeune, who offer a family perspective on their father; American attorney Martin Palmer, who recounts his role as an expert witness in legal proceedings regarding the legal status of the embryo; Dr. John Bruchalski, who discusses how Lejeune’s legacy has shaped his own obstetric practice; and George Weigel, writer and biographer of St. John Paul II, who reflects on the Pope’s friendship with Lejeune.
In addition, there is an unpublished interview with Birthe Lejeune, his widow, in which she reflects on her life with the geneticist.





