A phenocopy is a variation in
phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...
(generally referring to a single
trait) which is caused by environmental conditions (often, but not necessarily, during the organism's
development
Development or developing may refer to:
Arts
*Development hell, when a project is stuck in development
*Filmmaking, development phase, including finance and budgeting
*Development (music), the process thematic material is reshaped
*Photographi ...
), such that the organism's phenotype matches a phenotype which is determined by
gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...
tic factors. It is not a type of
mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mi ...
, as it is non-hereditary.
The term was coined by
Richard Goldschmidt
Richard Benedict Goldschmidt (April 12, 1878 – April 24, 1958) was a German-born American geneticist. He is considered the first to attempt to integrate genetics, development, and evolution. He pioneered understanding of reaction norms, gen ...
in 1935. He used it to refer to forms, produced by some experimental procedure, whose appearance duplicates or copies the phenotype of some mutant or combination of mutants.
Examples
The butterfly genus ''
Vanessa Vanessa may refer to:
Arts and entertainment
* ''Vanessa'' (Millais painting), an 1868 painting by Pre-Raphaelite artist John Everett Millais
* ''Vanessa'', a 1933 novel by Hugh Walpole
* ''Vanessa'', a 1952 instrumental song written by Bernie ...
'' can change phenotype based on the local temperature. If introduced to
Lapland they mimic butterflies localised to this area; and if localised to
Syria
Syria ( ar, سُورِيَا or سُورِيَة, translit=Sūriyā), officially the Syrian Arab Republic ( ar, الجمهورية العربية السورية, al-Jumhūrīyah al-ʻArabīyah as-Sūrīyah), is a Western Asian country loc ...
they mimic butterflies of this area.
The larvae of ''
Drosophila melanogaster
''Drosophila melanogaster'' is a species of fly (the taxonomic order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly" or "pomace fly". Starting with Ch ...
'' have been found to be particularly vulnerable to environmental factors which produce phenocopies of known mutations; these factors include temperature, shock, radiation, and various chemical compounds. In fruit fly, ''Drosophila melanogaster'', the normal body colour is brownish gray with black margins. A hereditary mutant for this was discovered by
T.H. Morgan
Thomas Hunt Morgan (September 25, 1866 – December 4, 1945) was an American evolutionary biologist, geneticist, Embryology, embryologist, and science author who won the Nobel Prize in Physiology or Medicine in 1933 for discoveries elucidating t ...
in 1910 where the body colour is yellow. This was a genotypic character which was constant in both the flies in all environments. However, in 1939, Rapoport discovered that if larvae of normal flies were fed with silver salts, they develop into yellow bodied flies irrespective of their genotype. The yellow bodied flies which are genetically brown is a variant of the original yellow bodied fly.
Phenocopy can also be observed in
Himalayan rabbits. When raised in moderate temperatures, Himalayan rabbits are white in colour with black tail, nose, and ears, making them phenotypically distinguishable from genetically black rabbits. However, when raised in cold temperatures, Himalayan rabbits show black colouration of their coats, resembling the genetically black rabbits. Hence this Himalayan rabbit is a phenocopy of the genetically black rabbit.
Baum P, Schmid R, Ittrich C, Rust W, Fundel-Clemens K, et al. (2010)
/ref>
Reversible and/or cosmetic modifications such as the use of hair bleach are not considered to be phenocopy, as they are not inherent traits.
See also
*Genocopy Genocopy is a trait that is a phenotypic copy of a genetic trait but is caused by a different genotype. When a genetic mutation or genotype in one locus results in a phenotype similar to one that is known to be caused by another mutation or genoty ...
References
{{Reflist
Genetics