June 13, 1926|
Montrouge, Hauts-de-Seine, France
|Died||April 3, 1994
|Institutions||French National Centre for Scientific Research|
|Alma mater||Collège Stanislas de Paris
Paris School of Medicine
|Notable awards||Kennedy Prize 1962
William Allen Award 1969
Prix Griffuel 1992
Discovering Trisomy 21 
In 1958, while working in Raymond Turpin’s laboratory, Jérôme Lejeune discovered that Down syndrome was caused by an extra chromosome on the 21st pair. The French Academy of Sciences published his scientific work on January 26, 1959. For the first time in world history, his discovery established a link between an intellectual disability and a chromosomal abnormality.
Origins of the discovery 
In the early 1950s, Lejeune joined the department headed by Dr. Turpin, who suggested that Lejeune focus his research on the causes of Down syndrome. As early as 1953, the two men showed a connection between an individual’s characteristics and his or her dermatoglyphs—a term referring to fingerprints and lines on the hand. The structure of these lines, which remain the same throughout the individual's life, is determined during the earliest stages of embryo development. As Lejeune and Turpin studied the hands of children witDown syndrome, they deduced that their dermatoglyphic anomalies appeared during embryo formation. After making many more observations, Dr. Lejeune concluded that the anomalies resulted from a chromosomal accident. Using a new tissue culture technique brought back from the United States by his colleague Marthe Gautier, Lejeune began working with her to count the number of chromosomes in children with Down syndrome.
The laboratory notebook begun by Dr. Lejeune on July 10, 1957 indicates that on May 22, 1958, he succeeded in showing, for the first time, the presence of 47 chromosomes in a child with Down syndrome. This was only two years after Tjio and Levan had proven that the human species has 46 chromosomes. On June 13, 1958, Dr. Lejeune identified an additional case, and a photo of the karyotype met with skeptical interest at the International Congress of Genetics in Montreal. The international community did not grasp the full impact of his discovery until January 26, 1959, when the French Academy of Sciences published the team’s first paper presenting three case studies of children with Down syndrome.
On March 16, 1959, another presentation to the Academy of Sciences confirmed the team’s initial publication, this time covering nine cases. In April 1959, the English team of Brown and Jacobs corroborated these results, citing the initial January 1959 publication by Lejeune, Gautier, and Turpin. “Mongolism” had become Trisomy 21.
The discovery opened up an enormous field of investigation for modern genetics and laid the foundation for a new discipline: cytogenetics. Until then, the laws of human heredity had been unable to explain Trisomy 21 and other anomalies in hereditary material. Jérôme Lejeune was now driven by a single ambition: to find a treatment that would bring relief to his patients as quickly as possible.
Several years later, a group of American scientists came to Paris to conduct an independent investigation of Dr. Lejeune’s discovery, and in 1962 the President of the United States personally presented him with the Kennedy Prize. In 1964, the first chair of human genetics was created at the Paris School of Medicine, and Jérôme Lejeune was named to fill it. The appointment was highly unusual: Only a groundbreaking discovery allowed a candidate to be named a professor of medicine without successfully completing a competitive residency examination.
In 1969, Lejeune's work earned him the William Allan Award, granted by the American Society of Human Genetics, the world’s highest honor in genetics. As of 2013[update] he was the only Frenchman to have won it. 
After receiving the Allan prize, he gave a talk to his colleagues which concluded by explicitly questioning the morality of abortion, an unpopular viewpoint in the profession. In a letter to his wife, Lejeune wrote "today, I lost my Nobel prize in Medicine".
The Researcher: Science in the Service of Medicine 
Fifty years ago, Lejeune identified the origin of Trisomy 21, restoring hope and dignity to tens of thousands of parents with children affected by the disease.
Continuing his work in genetics, he described several other diseases related to chromosomal abnormalities. In 1964 he identified Cri du Chat Syndrome, caused by a missing segment in the short arm of chromosome 5, and in 1966 he described 18q- Syndrome, which results from loss of the distal portion of the long arm of chromosome 18. Dr. Lejeune also discovered the Dr phenotype (a malformation syndrome in which a ring-shaped chromosome replaces chromosome 13), and he identified trisomies on chromosome 9 in 1970 and chromosome 8 in 1971.
Dr. Lejeune’s discoveries revolutionized genetics and paved the way for new therapeutic research— the work required to find cures once the origin of a disease is identified. But when diverted from their ultimate purpose, his discoveries also led to the elimination of children affected by genetic diseases.
Dr. Lejeune always viewed research as inseparable from treatment, and he was horrified as he gradually realized the consequences that misuse of his discovery would have for babies with [[Trisomy 21]]. As the American tendency to abort sick unborn children became more prevalent throughout Europe, he wrote, “They brandish chromosomal racism like the flag of freedom…. That this rejection of medicine—of the whole biological brotherhood that binds the human family—should be the only practical application of our knowledge of Trisomy 21 is beyond heartbreaking….” It was this realization that drove Jérôme Lejeune to begin his fight for the pro-life cause.
John Paul II and Jérôme Lejeune 
In 1975, after one of his public appearances in Paris on the beginning of life, Jérôme Lejeune met Wanda Poltawska, director of the Catholic Institute for the Family in Krakow.
Later that year, Dr. Poltawska contacted Dr. Lejeune twice, asking him to speak at conferences on the beginning of life that she was organizing with one of her close friends, Monsignor Karol Wojtyla, then Cardinal-Archbishop of Krakow.
On October 16, 1978, Wojtyla was elected Pope John Paul II. On May 13 1981, a few hours before the attempt on his life, he had lunch with Dr. Lejeune and his wife.
Afterward, Lejeune regularly traveled to Rome to meet with the Pope, to attend meetings of the Pontifical Academy of Sciences, and to participate in other church events, such as the 1987 Synod of Bishops. The Pope wanted to name Jérôme Lejeune as the president of a new pontifical academy that was dear to his heart: the Pontifical Academy for Life. Dr. Lejeune painstakingly drafted its bylaws and the oath of the Servants of Life that each member of the Academy must take.
Lejeune was diagnosed with lung cancer in November, 1993. He served as President of the Academy for only a few weeks before his death in April 1994. The Pope was grieved: “The words of Christ come to mind as we face the death of Dr. Jérôme Lejeune…. A death like this one bears even stronger witness to the Life that each of us is called to in Jesus Christ. Throughout our brother Jérôme’s life, this calling was a guiding principle. As a highly skilled biologist, he had a passion for life. He was one of the world’s great authorities in his field…. Today we face the death of a great 20th-century Christian, a man for whom defending life had become an apostolate….” (From the Vatican, April 4, 1994)
Lejeune has been named "Servant of God" by the Catholic Church, and his cause for sainthood is being postulated by the Abbey of Saint Wandrille in France.
Honors, awards and credentials 
Jérôme Lejeune received many distinctions during his lifetime. He was a member of:
- the French Institute’s Academy of Moral and Political Sciences
- the French Academy of Medicine
- the Pontifical Academy of Sciences
- the Lyncean Academy in Rome
- the American Academy of Arts and Sciences
- the Royal Swedish Academy
- the National Academy of Medicine in Argentina
- the University of Santiago, Chile
Dr. Lejeune held honorary doctorates from:
- University of Düsseldorf, Germany
- University of Pamplona, Spain
- University of Buenos Aires, Argentina
- Pontifical Catholic University of Chile
His international positions included:
Consulting expert on human genetics (1962)
- International Commission on Radiological Protection
Committee member (1963)
French expert to the Scientific Committee on the Effects of Atomic Radiation
- Life is a Blessing by Clara Lejeune ISBN 978-0-935372-59-5
- The Concentration Can by Jérôme Lejeune ISBN 978-0-89870-394-8
- The Tiniest Humans by Robert L. Sassone, Jerome Lejeune, Albert W. Liley ISBN 1-890712-17-5
- Jérôme Lejeune by Anne Bernet ISBN 978-2-7509-0029-8
- Le Professeur Lejeune - Fondateur de la Génétique Moderne by Jean-Marie Le Méné ISBN 978-2-7289-0859-2
- J. LEJEUNE, M. GAUTIER and R. TURPIN. Les chromosomes humains en culture de tissus. C. R. Acad. Sciences, January 26, 1959
- The Jérôme Lejeune Foundation
- International Conference Jerome Lejeune
- Institut Lejeune
- The Lejeune Foundation USA