The configuration of an organic molecule containing a double bond between two carbon atoms, where the largest, most complex R groups attached to each carbon are on opposite sides. H3C H / C=C / H CH3 -OR-The configuration of an organic molecule containing a ring, where the largest, most complex R groups attached to each carbon are on opposite sides: H3C H | ___ / | // \ [ring viewed edge-on] | \___/ / | /--- H CH3 | H3C CH3 These configurations are the opposite of cis configuration. A genetics term meaning that the changes in gene expression are due to something acting on the gene from a distance, or from an unrelated location, rather than on the same strand of DNA. Two mutations in different genes coding for the same phenotype which are on opposite homologous chromosomes (as opposed to the cis configuration where both of the mutations are on the same homologue).