1909

Dutch botanist Wilhelm Johannsen coins word “gene” to denote a (Mendelian) unit of heredity. “The word was created to mark a function; it was an abstraction. A gene was defined by what a gene does: it was a courier of hereditary information.” But the abstraction launched “a thousand questions,” e.g., What was the chemical and physical nature of the gene? How were genes transmitted? Where did they reside? and so forth Mukherjee II, loc 71ff.).