As one of the early medical geneticists, Eric Engel (Fig. 1) will be remembered by most for his scientific insights. For us, he is best remembered as a highly supportive mentor, a deep thinker, and a committed and caring physician.
Initially trained in his native Geneva as an internist before specializing in endocrinology, he moved with his family to Boston for a fellowship at Massachusetts General Hospital in 1960. While mastering the language and culture of his new country, he became interested in Turner syndrome, which then led him to focus on chromosomal analysis as a diagnostic and research tool. Three years later, he became a faculty member at Vanderbilt University School of Medicine, where he developed a clinical program in medical genetics and a diagnostic cytogenetics laboratory. He published widely on cytogenetic and clinical findings in sex chromosome disorders and in cancer cytogenetics, particularly leukemias. He was a key contributor to the literature on a wide range of chromosomal syndromes, helping to delineate the clinical and cytogenetic findings resulting from several deletions and duplications.
Through his attempts to understand the mechanisms leading to genetic disorders, Eric's most innovative contribution to the field of genetics was his hypothesis that genetic disorders could occasionally result from uniparental disomy. At the time, the concept that the two members of a chromosomal pair could both derive from a single parent was a radical (and at that time purely theoretical) idea. Given the high rate of chromosomal anomalies in human germ cells, he reasoned, it must sometimes happen that two abnormal germ cells would meet and “correct” each other, resulting in a normal chromosome number, but with both members of a disomic pair coming from the same parent. This hypothesis proved difficult to publish and was not widely accepted for nearly a decade. It was this Journal that ultimately published Engel's seminal paper on uniparental disomy and isodisomy [Engel, 1980; Fig. 2]. With the advent of molecular genetic techniques, the concept was proven correct for the first time when a patient with cystic fibrosis was shown to have only one carrier parent [Spence et al., 1988]. This innovative concept of uniparental disomy has led to the mapping of numerous genetic disorders and to the unraveling of mechanisms causing several important genetic syndromes, including Prader–Willi, Angelman and Beckwith–Wiedemann syndromes, which in turn resulted in recognition that genomic imprinting is a significant cause of human disease.
It was during his early years at Vanderbilt that both of us first came in contact with Eric and were inspired to embark on careers in medical genetics, indelibly influenced by his enthusiasm, intellectual curiosity, and supportive mentoring. Eric later returned to Geneva in 1978 as Director of the University Institute of Medical Genetics, where one of us (C.D.D.) had the privilege of working with him for over a decade in his home country.
Although he officially retired in 1991, Eric continued to conduct research, write, and speak on uniparental disomy and genomic imprinting. Until just a few months before his death from cancer last fall at the age of 85, he continued to pursue intellectual and artistic pursuits, writing poetry and prose in his beloved first language, French. Eric is survived by wife Mireille, children Olivier, Severine and Fabienne, and brother Pierre, a family that still spans the American and European continents.
To those of us who knew him well, Eric Engel was much more than an outstanding medical geneticist and innovator, the “father” of uniparental disomy. He was also a connoisseur of art, music and language and, in his later years, a prolific writer. He was a humanist who brought passion, compassion and great intellectual abilities to bear on his medical and academic practice, being extremely caring and respectful of his patients and dedicated to his students. He was a lifelong learner, with a constantly inquiring mind. And he was an extraordinary mentor and role model. He will live on in our hearts and in the character of our clinical genetics practices and research and that of our trainees.