Dictionary > Allelic exclusion

Allelic exclusion

Allelic exclusion
(Science: cell biology, genetics) The process whereby one or more loci on one of the chromosome sets in a diploid cell is inactivated (or destroyed) so that the locus or loci is (are) not expressed in that cell or a clone founded by it.
For example in mammals one of the x chromosome pairs of females is inactivated early in development (see Lyon hypothesis) so that individual cells express only one allelic form of the product of that locus. Since the choice of chromosome to be inactivated is random, different cells express one or other of the x chromosome products resulting in mosaicism.
The process is also known to occur in immunoglobulin genes so that a clone expresses only one of the two possible allelic forms of immunoglobulin.


You will also like...

Control of body movement
Control of Body Movement

Some of the body movements can be controlled at will, others cannot. The body has a motor program, which is the pattern ..

New Zealand Fauna
New Zealand’s Unique Fauna

Meet some of New Zealand's unique fauna, including endemic insects, frogs, reptiles, birds, and mammals, and investigate..

running freshwater community
Running Water Freshwater Community Factors

This tutorial noted some of the physical and chemical factors that provide the framework of a running water community in..

Types and Causes of Brain Damage
Types and Causes of Brain Damage

This tutorial describes the different types and causes of brain damage. Find out how genetics, physical injury, lack of ..

Still Water Animals
Still Water Animals

Animals living in aquatic habitats have diversified and evolved through time. They eventually occupy ecological niches a..

Population Regulation in an Ecosystem
Population Regulation in an Ecosystem

With regard to the population size of a species and what factors may affect them, two factors have been defined. They ar..

Related Articles...

No related articles found

See all Related Topics