<molecular biology> A mutant gene which causes the activity that it influences to increase. ... (11 Jan 1998) ... 
(hi´pәr-morf) a mutant gene characterized by an increase in the activity it influences. See also hypomorph.
Type: Term Pronunciation: hī′pĕr-mōrf Definitions: 1. Person whose sitting height is low in proportion to standing height, owing to excessive length of limb. 2. A mutant gene that causes an increase in the activity controlled by the gene.