Trans | The term proposed by Haldane (1941), by analogy with chemical isomerism, to describe a double heterozygote in repulsion phase, that is, with the dominant factors derived from opposite parents. The term is used chiefly for closely-linked mutants, to which it was first applied by Pontecorvo (1950). The trans configuration for two recessive mutants, 1 and 2, is +2/1+, where + stands for the wild-type, and the slash separates the contributions from the two parents. (Cf. Cis.) |