On January 21, 2021, the Vatican announced that Dr. Jerome Lejeune’s cause for canonization has moved forward, declaring him “venerable.” Dr. Lejeune was the French doctor who in 1958 discovered the presence of an extra copy of chromosome #21 in Down syndrome, known also as Trisomy 21. To his regret, his discovery was used to end the life of many Down syndrome children in the womb.
As mentioned in a previous post, in the 1970’s this discovery was combined with a new technology, the ultrasound, which had become useful in the process of amniocentesis. Amniocentesis was used to identify these children (called “genetic accidents”) followed by selective abortion.
For the rest of his career, Dr. Lejeune valiantly defended the dignity and value of all human life, especially “his” Down syndrome children. In fact, in 1974, during an acceptance speech for the prestigious William Allan Memorial Award, he spoke out passionately against its use for selective abortion. He stated that even those “disinherited” members of our race deserve our compassion and care:
“But should we capitulate in the face of our own ignorance and propose to eliminate those we cannot help?... For millennia, medicine has striven to fight for life and health and against disease and death… Our duty has always been not to inflict the sentence but to try to commute the pain.” —Dr. Jerome Lejeune
Apparently, he told his wife afterward: “Today, I lost my Nobel Prize in Medicine.” His prediction turned out to be true.
In a summary of his biography, Life is a Blessing, we read the following description:
“A man of faith, a man with heart, he was also a very great physician and an immensely gifted scientist. His daughter Clara presents here the private man: the happy father of a family, surrounded by children and grandchildren, a great Christian marked by a discreet and radiant faith, a man of culture inspired with a great sense of humor, but above all a man of courage and of great relevance who knew how to live in harmony with himself and with those whom he loved, without ever abandoning the battle to defend the smallest (i.e. the pre-born) and the mentally handicapped.” —Life is a Blessing
For a description of some of his other scientific discoveries, please go to this link.
Is our destiny written in our genes?
The answer to this question is yes and no.
Dr. Lejeune’s work opened up investigations into the genetic sources of disease. When the source is a single gene, it is easier to identify and study. But the cause of many diseases, and of many of our characteristics, result from the interplay of many and varied genes. With the incredible growth in this science of epigenetics—how environmental and other factors influence genetic expression—one thing has become clear: our DNA does not automatically dictate the development of our characteristics. This includes how tall you are going to be or whether you will develop a mental health condition.
This interplay is often discussed using the phrase, “nature versus nurture”—nature being our genes and nurture being the presence of internal and external factors that affect their expression. Perhaps you remember the terms genotype and phenotype from high school or college biology, where the phenotype refers to the characteristic that actually develops.
Why is knowing the function and location of genes important?
Perhaps you have heard of the Human Genome Project, completed in 2003 under the direction of Dr. Francis Collins, current head of the National Institute of Health. This project identified all of the roughly 25,000 encoding genes in the human genome.
Genomic sequencing, however, is not limited to humans. Scientists have sequenced the genomes of approximately 250 species of animals, from the simple sea urchin and honey bee, to chickens and chimpanzees.
Why should we care?
According to the National Human Genome Research Institute, the study of comparative genomics:
“...pinpoints genes that are essential to life and highlights genomic signals that control gene function across many species. It helps us to further understand what genes relate to various biological systems, which in turn may translate into innovative approaches for treating human disease and improving human health.”
In other words, when genetic markers of health and disease are known, scientists can identify effective therapeutic targets and develop strategies to prevent the disabilities and diseases for which these markers are responsible.
Another result of the Human Genome Project was the development of a new research tool known as the Genome Wide Association Study (GWAS). This method compares the genetic sequences of individuals known to have a particular condition to those who do not. By doing this comparison using a large population, it is possible to identify small genetic variations (a single base pair change, often called a SNP, small nucleotide polymorphism). The genes of these “snips” (SNPs) are then investigated as potential causes of a condition. Currently, over 5 million such SNPs have been identified for a variety of diseases and mental health conditions.
Manhattan plots for the GWAS results for eye pigmentation
How does this information get used in research?
An example can be found in the work of Dr. Thalia Eley of King's College London. She and her colleagues are collecting DNA samples from individuals suffering anxiety and depression, hoping to identify small variations that might be linked to the development of these conditions. In Dr. Eley’s earlier work, she and her colleague identified the impact of negative life events on the development of depression. Then more recent studies discovered that differences in the allele length of a serotonin transporter gene moderated responses to negative life events. (Serotonin is a hormone affecting our mood and sense of well-being.) Dr. Eley and colleagues hope to acquire enough data to identify other risk alleles and develop interventions for each genotypic patient. Medicine is getting that specific!
Back to Dr. Lejeune
Shortly before he died of lung cancer in 1994, Dr. Lejeune lamented:
“I was the doctor who was supposed to cure them and, as I leave, I feel I am abandoning them.”
They have not been abandoned.
It is indeed heartening to learn that many doctors remain inspired by Lejeune’s efforts on behalf of his patients and that research continues in ways to maximize the potential of those born with Down syndrome and perhaps, through gene editing, limit the disabilities caused by the extra chromosome.
After Dr. Lejeune’s funeral, Bruno, a young man with Down syndrome whose karyotype had helped identify the extra chromosome, expressed his gratitude for a different kind of a cure:
“Thank you, my professor, for all that you have done for my father and my mother. Thanks to you, I am proud to be me.” —Bruno, as quoted from Life is a Blessing
Dr. Lejeune reminds us that life is a blessing—for all of us!
Cover Image: Fondation Jérôme Lejeune, CC BY-SA 3.0, via Wikimedia Commons; Image of Dr. Lejeune with boy: Denis-Soto, CC BY-SA 3.0, via Wikimedia Commons; Manhattan plots for the GWAS results for the eye pigmentation / Sophie I. Candille , Devin M. Absher, Sandra Beleza, Marc Bauchet, Brian McEvoy, Nanibaa’ A. Garrison, Jun Z. Li, Richard M. Myers, Gregory S. Barsh, Hua Tang , Mark D. Shriver, CC BY 4.0, via Wikimedia Commons