無形質の、無定形態の

WordNet

characterized by metamorphosis or change in physical form or substance
of or relating to metamorphosis (especially of rocks); "metamorphic stage"; "marble is a metamorphic rock that takes a high polish" (同)metamorphous
pertaining to gradual evolution from one type of organism to another
pertaining to a kind of distorting optical system; "an anamorphic lense"
rock altered by pressure and heat
not metamorphic

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変態の,変態を特色とする / 変成の

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/09/15 12:14:24」(JST)

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Neomorph redirects here. It is also one of the post-human types of persons in the novel Eon by Greg Bear.

Hermann J. Muller (1890–1967), who was a 1946 Nobel Prize winner, coined the terms amorph, hypomorph, hypermorph, antimorph and neomorph to classify mutations based on their behaviour in various genetic situations.^[1] These classifications are still widely used in Drosophila genetics to describe mutations. For a more general description of mutations, see mutation, and for a discussion of allele interactions, see dominance relationship.

Key: In the following sections, alleles are referred to as +=wildtype, m=mutant, Df=gene deletion, Dp=gene duplication. Phenotypes are compared with '>', meaning 'phenotype is more severe than'

Loss of function

Amorph

Amorphic describes a mutation that causes complete loss of gene function.^[1] Amorph is sometimes used interchangeably with "genetic null". An amorphic mutation might cause complete loss of protein function by disrupting translation ("protein null") and/or preventing transcription ("RNA null").

An amorphic allele elicits the same phenotype when homozygous and when heterozygous to a chromosomal deletion or deficiency that disrupts the same gene.^[2] This relationship can be represented as follows:

m/m = m/Df

An amorphic allele is commonly recessive to its wildtype counterpart. It is possible for an amorph to be dominant if the gene in question is required in two copies to elicit a normal phenotype (i.e. haploinsufficient).

Hypomorph

Hypomorphic describes a mutation that causes a partial loss of gene function.^[1] A hypomorph is a reduction in gene function through reduced (protein, RNA) expression or reduced functional performance, but not a complete loss.

The phenotype of a hypomorph is more severe in trans to a deletion allele than when homozygous.^[2]

m/DF > m/m

Hypomorphs are usually recessive, but occasional alleles are dominant due to haploinsufficiency.

Gain of function

Hypermorph

A hypermorphic mutation causes an increase in normal gene function.^[1] Hypermorphic alleles are gain of function alleles. A hypermorph can result from an increase in gene dose (a gene duplication), from increased mRNA or protein expression, or constitutive protein activity.

The phenotype of a hypermorph is worsened by increasing the wildtype gene dose, and is reduced by lowering wildtype gene dose.^[2]

m/Dp > m/+ > m/Df

Antimorph

Antimorphs are dominant mutations that act in opposition to normal gene activity.^[1] Antimorphs are also called dominant negative mutations.

Increasing wildtype gene function reduces the phenotypic severity of an antimorph, so the phenotype of an antimorph is worse when heterozygous than when in trans to a gene duplication.^[2]

m/+ > m/Dp

An antimorphic mutation might affect the function of a protein that acts as a dimer so that a dimer consisting of one normal and one mutated protein is no longer functional.

Neomorph

A neomorphic mutation causes a dominant gain of gene function that is different from the normal function.^[1] A neomorphic mutation can cause ectopic mRNA or protein expression, or new protein functions from altered protein structure.

Changing wildtype gene dose has no effect on the phenotype of a neomorph.^[2]

m/Df = m/+ = m/Dp

References

^ ^a ^b ^c ^d ^e ^f Muller, H. J. 1932. Further studies on the nature and causes of gene mutations. Proceedings of the 6th International Congress of Genetics, pp. 213–255.
^ ^a ^b ^c ^d ^e Wilkie, A. O. 1994. The molecular basis of genetic dominance. Journal of Medical Genetics 31: 89-98. [1]

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1. 重度複合型免疫不全（SCID）：特定の欠損 severe combined immunodeficiency scid specific defects
2. 複合免疫不全 combined immunodeficiencies

English Journal

Dominant gain-of-function STAT1 mutations in FOXP3 wild-type immune dysregulation-polyendocrinopathy-enteropathy-X-linked-like syndrome.

Uzel G, Sampaio EP, Lawrence MG, Hsu AP, Hackett M, Dorsey MJ, Noel RJ, Verbsky JW, Freeman AF, Janssen E, Bonilla FA, Pechacek J, Chandrasekaran P, Browne SK, Agharahimi A, Gharib AM, Mannurita SC, Yim JJ, Gambineri E, Torgerson T, Tran DQ, Milner JD, Holland SM.Author information Laboratory of Clinical Infectious Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1684, USA.AbstractBACKGROUND: Mutations in signal transducer and activator of transcription (STAT) 1 cause a broad spectrum of disease, ranging from severe viral and bacterial infections (amorphic alleles) to mild disseminated mycobacterial disease (hypomorphic alleles) to chronic mucocutaneous candidiasis (CMC; hypermorphic alleles). The hypermorphic mutations are also associated with arterial aneurysms, autoimmunity, and squamous cell cancers.
The Journal of allergy and clinical immunology.J Allergy Clin Immunol.2013 Jun;131(6):1611-23. doi: 10.1016/j.jaci.2012.11.054. Epub 2013 Mar 25.
BACKGROUND: Mutations in signal transducer and activator of transcription (STAT) 1 cause a broad spectrum of disease, ranging from severe viral and bacterial infections (amorphic alleles) to mild disseminated mycobacterial disease (hypomorphic alleles) to chronic mucocutaneous candidiasis (CMC; hype
PMID 23534974

Mineralogy and characterization of deposited particles of the aero sediments collected in the vicinity of power plants and the open pit coal mine: Kolubara (Serbia).

Cvetković Ž, Logar M, Rosić A.Author information Geological Institute of Serbia, Rovinjska 12, 11 000 Belgrade, Serbia. c-zeljko@ikom.rsAbstractIn this paper, particular attention was paid to the presence of aerosol solid particles, which occurred mainly as a result of exploitation and coal combustion in the thermal power plants of the Kolubara basin. Not all of the particles created by this type of anthropogenic pollution have an equal impact on human health, but it largely depends on their size and shape. The mineralogical composition and particle size distribution in the samples of aero sediments were defined. The samples were collected close to the power plant and open pit coal mine, in the winter and summer period during the year 2007. The sampling was performed by using precipitators placed in eight locations within the territory of the Lazarevac municipality. In order to characterize the sedimentary particles, several methods were applied: microscopy, SEM-EDX and X-ray powder diffraction. The concentration of aero sediments was also determined during the test period. Variety in the mineralogical composition and particle size depends on the position of the measuring sites, geology of the locations, the annual period of collecting as well as possible interactions. By applying the mentioned methods, the presence of inhalational and respiratory particles variously distributed in the winter and in the summer period was established. The most common minerals are quartz and feldspar. The presence of gypsum, clay minerals, calcite and dolomite as secondary minerals was determined, as well as the participation of organic and inorganic amorphic matter. The presence of quartz as a toxic mineral has a particular impact on human health.
Environmental science and pollution research international.Environ Sci Pollut Res Int.2013 May;20(5):3034-49. doi: 10.1007/s11356-012-1154-z. Epub 2012 Oct 2.
In this paper, particular attention was paid to the presence of aerosol solid particles, which occurred mainly as a result of exploitation and coal combustion in the thermal power plants of the Kolubara basin. Not all of the particles created by this type of anthropogenic pollution have an equal imp
PMID 23054761

A novel indirect defence in Brassicaceae: structure and function of extrafloral nectaries in Brassica juncea.

Mathur V, Wagenaar R, Caissard JC, Reddy AS, Vet LE, Cortesero AM, Van Dam NM.Author information Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), PO Box 50, 6700 AB Wageningen, The Netherlands. vmathur@svc.ac.inAbstractWhile nectaries are commonly found in flowers, some plants also form extrafloral nectaries on stems or leaves. For the first time in the family Brassicaceae, here we report extrafloral nectaries in Brassica juncea. The extrafloral nectar (EFN) was secreted from previously amorphic sites on stems, flowering stalks and leaf axils from the onset of flowering until silique formation. Transverse sections at the point of nectar secretion revealed a pocket-like structure whose opening was surrounded by modified stomatal guard cells. The EFN droplets were viscous and up to 50% of the total weight was sugars, 97% of which was sucrose in the five varieties of B. juncea examined. Threonine, glutamine, arginine and glutamate were the most abundant amino acids. EFN droplets also contained glucosinolates, mainly gluconapin and sinigrin. Nectar secretion was increased when the plants were damaged by chewing above- and belowground herbivores and sap-sucking aphids. Parasitoids of each herbivore species were tested for their preference, of which three parasitoids preferred EFN and sucrose solutions over water. Moreover, the survival and fecundity of parasitoids were positively affected by feeding on EFN. We conclude that EFN production in B. juncea may contribute to the indirect defence of this plant species.
Plant, cell & environment.Plant Cell Environ.2013 Mar;36(3):528-41. doi: 10.1111/j.1365-3040.2012.02593.x. Epub 2012 Sep 9.
While nectaries are commonly found in flowers, some plants also form extrafloral nectaries on stems or leaves. For the first time in the family Brassicaceae, here we report extrafloral nectaries in Brassica juncea. The extrafloral nectar (EFN) was secreted from previously amorphic sites on stems, fl
PMID 22889298