Genes and Genotypes

No hypothesis concerning the nature of this 'something' shall be advanced thereby or based thereon. Therefore it appears as most simple to use the last syllable 'gen' taken from Darwin's well-known word pangene since it alone is of interest to use, in order thereby to replace the poor, more ambiguous word, 'Anlage'. Thus, we will say for 'das pangene' and 'die pangene' simply 'Das Gen' and 'Die Gene,' The word Gen is fully free from every hypothesis; it expresses only the safely proved fact that in any case many properties of organisms are conditioned by separable and hence independent 'Zustiinde,' 'Grundlagen,' 'Anlagen'—in short what we will call 'just genes'—which occur specifically in the gametes.

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This constitution we designate by the word genotype. The word is entirely independent of any hypothesis; it is fact, not hypothesis that different zygotes arising by fertilisation can thereby have different qualities, that, even under quite similar conditions of life, phenotypically diverse individuals can develop.

The origin of the words.