obsolete phenotype bias true MI:1289 2013-06-05T21:15:34Z PSI-MI orchard OBSOLETE: An effect when two individual perturbations result in opposite mutant phenotypes (relative to wild type) and their combination results in a phenotype that is intermediate to the individual mutant phenotypes, but greater or less than wild type. With respect to any single quantifiable phenotype, this may be expressed as an inequality as: (a < wt < b) AND (a < ab < b) AND (ab != wt) where 'a' and 'b' are the observed phenotype values of the individual perturbations, 'ab' is the observed phenotype value of the double perturbation, and 'wt' is the wild type phenotype value.