Dictionary > Hypomorphic mutation

Hypomorphic mutation

(genetics) A type of mutation wherein the change in gene leads to the partial loss of the normal (wild-type) gene function, such as by reduced expression (of protein or RNA)
Mutations involving recessive genes often results in the reduction or elimination of the gene function. When the function of the gene is completely eliminated the mutation is referred to as amorphic. But when the mutation leads to only a reduction in the gene function it is called hypomorphic. Thus, in the latter type of mutation, the function of the gene is not eliminated but reduced. Other types of mutations based on the effects on the phenotypes are antimorphic mutation, hypermorphic mutation, and neomorphic mutation. Both amorphic and hypomorphic mutations are associated with the loss of function due to a gene mutation. The other three, in contrast, are related to the “gain of function” of the gene. The terms were coined by the American geneticist, Hermann J. Muller.1

  • partial loss-of-function mutation
  • weak mutation
  • hypomorph


See also:


1Muller, H. J. 1932. Further studies on the nature and causes of gene mutations. Proceedings of the 6th International Congress of Genetics, pp. 213–255.

You will also like...

3D rendering of an antibody
Passive and Active Types of Immunity

Lymphocytes are a type of white blood cell capable of producing a specific immune response to unique antigens. In thi..

Photosynthesis and respiration
Plant Metabolism

Plants are responsible for incredible feats of molecular transformation. Plant processes, such as photosynthesis, photop..

Plant meristem
Plant Meristems and Growth

In plants, growth occurs in meristems, which are the site of repeated cell division of unspecialized cells. These cells ..

Kidneys and Regulation of Water and Inorganic Ions

The kidneys are responsible for the regulation of water and inorganic ions. Read this tutorial to learn about the differ..

Angle Oak Tree
Seed Plants

Seed plants are vascular plants. They differ from the other vascular plants in producing seeds that germinate into a new..

Early Earth
The Origins of Life

This tutorial digs into the past to investigate the origins of life. The section is split into geological periods in the..