Zur Wissenschaftsgeschichte des biologischen Terminus ‚Gen‘

Abstract

Contemporary philosophy of science places the origins of the predominant attributes of the term ‘gene’ in the year 1900 when Gregor Mendel’s work was rediscovered. After that, his phrase of discrete units of heredity, which he had developed on purely statistical and formal grounds, was replaced by that of morphologically definable and experimentally verifiable factors on chromosomes. Yet it was the speculative biology of the second half of the 19th century that opened up the epistemic sphere for a new conception of heredity: heredity as the transmission of particulate, hereditable material units with a tendency for self-preservation. This approach helped the then young discipline of biology get geared towards pure science with the aim of dissociating its terminology, which was deduced a priori, from the preconceptions of natural philosophy. In the early 20th century, the era of classical genetics, experimental systems were developed which, by means of experiments on model organisms, defined the hereditary particles, which had been speculatively assumed and the terminology for which had been developed in strict argumentations in the 19th century, more precisely and, in the 1940s, associated them with nucleic acid: physically detectable, material units without any final causality. They were said to be stable and, at the same time, mutable as well as capable of self-reproductivity, self-selectivity and memory. The term ‚code mechanism‘ paraphrases this dimension formerly unknown to physics. DNA epitomizes the perfect biological principle. The gene is declared the reason for the spontaneity and the specificity of organic matter. Still this concept includes components that have been framed by the biology of the 19th century. The most recent conception of the gene is not free from teleological anthropomorphisms. The sheer physical automatism gives the picture of molecular initial conditions that would contain the causes for the outcome of the development of the organism with all its variability, conceptualized by the term memory.