The holist tradition in twentieth century genetics. Wilhelm Johannsen's genotype concept.

The terms 'genotype', 'phenotype' and 'gene' originally had a different meaning from that in the Modern Synthesis. These terms were coined in the first decade of the twentieth century by the Danish plant physiologist Wilhelm Johannsen. His bean selection experiment and his theoretical analysis of the difference between genotype and phenotype were important inputs to the formation of genetics as a well-defined special discipline.