Waardenburg, Petrus Johannes
(1886-1979) Dutch ophthalmologist and medical geneticist who described the condition now known as Waardenburg syndrome. The syndrome is characterized by wide bridge of the nose owing to lateral displacement of the inner canthus of each eye, pigmentary disturbance (frontal white blaze of hair, eyes of different color, white eye lashes, leukoderma), and cochlear deafness.
Waardenburg made many other contributions to genetics, In 1932 he suggested that Down syndrome might be due to a chromosome abnormality, which was confirmed in 1959 by Jerome Lejeune and colleagues in Paris.
Dr. Waardenburg did his medical studies at the University of Utrecht, trained in ophthalmology, and wrote his doctoral thesis on the hereditary basis of features of the eye. His interest in genetics was reinforced when his wife gave birth to monozygous twin daughters. He extended his research to twin studies.
In 1947 at a meeting of the Dutch Ophthalmological Society in Utrecht, Waardenburg presented a deaf-mute tailor with what is now called Waardenburg syndrome. The first description of this syndrome, however, may have been recorded in 1888 by the German writer Karl May.
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