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June 13 The Doctor who discovered the causes of Downs Syndrome and then became their defender

Jérôme Jean Louis Marie Lejeune was born today in 1926. He would become a medical doctor and was a pioneering researcher all his life. He would go down in history as the Doctor who identified the double chromosome that was the cause of what had become known as 'Downs syndrome'. However his work with Downs children turned him to a passionate advocate and defender of them and he was distraught when he discovery was used widely in prenatal tests routinely as a step to aborting the foetus.


Moved by the struggles experienced by children with Downs syndrome and their families he decided to dedicate his life to them. As medicine was powerless to help these children he would engage in research to find the causes of Down Syndrome so that the medical profession could understand the condition and bringing awareness to the challenges they face. Motivated by his faith which instilled in him the dignity and sacredness of all life, he would campaign tirelessly against abortion and became a close adviser of Pope John Paul II. His cause for canonisation is now open.

In 1958, while working in Raymond Turpin’s laboratory Jérôme reported that he had discovered that Down syndrome was caused by an extra copy of chromosome 21. This was a breakthrough, as only two years earlier in Sweden Joe Hin Tijo and Albert Levan had proven that the human species has 46 chromosomes. Lejeuness demonstration of the presence of 47 chromosomes in a child with Down syndrome was 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 26 January 1959, when the French Academy of Sciences published the team’s first paper presenting three case studies of children with Down syndrome] This discovery was the first time that a defect in intellectual development was shown to be linked to chromosomal abnormalities

Lejeune’s discoveries paved the way for new therapeutic research into how changes in gene copy number could cause disease. Although the results of his research should have helped medicine to advance towards a cure, in reality they are often used to identify children carrying these conditions as early as possible, usually with the aim of terminating pregnancy.

The rapid development of prenatal diagnosis of chromosome abnormalities and thence to abortions of affected pregnancies was very distressing to Lejeune, a devout Catholic, and led him to begin his fight for the anti-abortion cause. He was propelled to the forefront of advocating for the protection of the unborn with Down syndrome and gave hundreds of conferences and interviews across the globe in defence of life. In France, Lejeune opposed Peyret’s laws in 1970 to render legal the interruption of pregnancy in case of foetal abnormalities. He also opposed the Veil Law ("Loi Veil" 1975) authorizing voluntary interruption of pregnancy. He was courageous in speaking about his deep convictions and would use the platforms that the many awards he won would give him. After receiving the William Allan Award of $25,000 and an engraved medal from the American Society of Human Genetics, Lejeune 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."

In 1975, after one of his public appearances in Paris on the beginning of life, Lejeune met the director of the Catholic Institute for the Family in Kraków a close friend of Monsignor Karol Wojtyla, then Cardinal-Archbishop of Krakow. Three years later he was elected Pope John Paul II. Afterward, Lejeune regularly traveled to Rome to meet with the Pope, to attend meetings of the Pontifical Academy of Sciences the Pope appointed Lejeune as the president of a new pontifical academy that was dear to his heart: the Pontifical Academy for Life. Lejeune painstakingly drafted its bylaws and the oath of the Servants of Life that each member of the Academy must take.

Sadly, Lejeune was diagnosed with lung cancer in November 1993 and was only able to serve as the president of the Academy for a few weeks before his death in April 1994. A few years later, during his visit to Paris for World Youth Day 1997, John Paul II visited Lejeune’s grave in Châlo-Saint-Mars. 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. On 21 January 2021, Pope Francis declared Lejeune's heroic virtues, and Lejeune was named "Venerable"


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