Gregor Mendel’s legacy in quantitative genetics
Trudy F. C. Mackay, Robert R. H. Anholt
Abstract
The field of genetics was born with the publication in 1866 of Gregor Mendel's Experiments in Plant Hybridization Working with the garden pea, Pisum sativum, Mendel chose 7 "characters" (polymorphic loci each affecting a different phenotype in today's parlance) that "permit of a sharp and certain separation," excluding those for which "the difference is of a 'more or less' nature, which is often difficult to define" Mendel chose these loci because the hybrid (F 1 ) between the homozygous parental genotypes (to use modern terminology) was indistinguishable from one of the parents; i.e., one of the alleles was dominant and the other recessive (Mendel's original terms). He excluded phenotypes that were intermediate between the 2 parents in the F 1 hybrid.