Talk:Phenotype

Untitled
Can anyone explain how the epigenome affects the way the genotype translates to the phenotype?

Who defined what a phenotype is ?
"...A phenotype is any observable characteristic of an organism, such as its morphology, development, biochemical or physiological properties, or behavior..." And who is the person that says so?

Put a bunch of marbles in a bag. Pick one out without looking at it. Would this be a random selection or a selection at random ? It would be a selection at random but the intent is that consciousness is involved. Usually the symbol string "random" is not associated with consciousness. Likewise what is the intent with phenotype, if random can be both used in a sentence with either the intent of purposelessness and purpose then imagine the fun you can have with this undefined word phenotype. What is the concept with the word 'random', 'fitness', 'genotype' and 'selection' as used in sentences? The concept or Pragmatics is the issue and only conscious beings can have concepts. TongueSpeaker (talk) 18:02, 29 October 2008 (UTC)
 * Curt Stern, Principles of Human Genetics, W.H. Freeman and Co., San Francisco, CA, USA, 1950, p. 36:

"...helps us in gaining an insight into the interrelation between genes and 'characters', which is an important aspect of human genetics. A 'character' or trait may be defined as any observable feature of the developing or the fully developed individual: A biochemical property, a cellular form or process, an anatomical structure, an organ function, or a mental characteristic. The genic content of the nuclei of a given individual and his 'external' appearance are obviously different concepts. The word 'external' signifies that the characters are derived from genic action. They are removed from the genes by at least one and, often, numerous steps. For the genetic constitution, the term genotype has been coined; for the external appearance, the term phenotype is used."
 * Hope this helps. Unfortunately, Stern does not provide a reference for the definition of "phenotype", but this is the oldest mention I have found. This quote should also explain the query below about the ABO blood groups: the A and B antigens (or their absence in O) are at least one step removed from the A, B, and O alleles of the I gene. (See the ABO article for more details). --Crusio (talk) 19:51, 29 October 2008 (UTC)

Merge proposal
Please discuss merger at Talk:Trait

Resolved Discussion: added to article
Phenotype can be easily summarised as

PHENOTYPE = GENOTYPE + ENVIRONMENTAL FACTORS
 * Who is the individual that has formally established this? Theories are always formally established, ask Newton and Maxwell.TongueSpeaker (talk) 17:47, 1 November 2008 (UTC)

It would be misleading to say that the phenotype is coded solely by the genotype. The effect of environmental factors on the phenotype can be difficult to assess and can vary widely according to which phenotype you are examining but are still essential in determining every phenotype.

Without sufficient warmth, water or light, plants will fail to grow normally regardless of genotype. Thalidomide victims have a normal genotype, but because of an environmental factor (the presence of thalidomide) they have an unfortunate abnormal phenotype. In the case of some animals, sex determination relies upon environmental factors.

Kurzon (03 May 2005) - I don't quite like that equation, as it can be a bit misleading: one could mistakenly think that the phenotype is merely the genotype and environmental factors considered simultaneously, not their consequence for the organism. It's not a big issue - I think most readers will get it - but is there a better way of expressing this? Perhaps an arrow ( -> ) like in chemistry equations in place of the equals sign?

You could say instead that phenotype is a function of genotype and environmental factors. Also, the "nuanced" version including "random variation" might be misleading. Isn't such "random" variation due to environmental factors which are difficult to track? -- Alan McBeth 15:57, 21 October 2005 (UTC)

Total Lack of understanding
Can someone please give an example of phenotypes or a simpler explanation. Having read this articial a few times i still am very unclear what a phenotype is. Is it just random variation between features. dont all animials display this ? (Gnevin 21:44, 26 April 2006 (UTC))
 * The definition is blurred. A phenotype is not a trait: a phenotype manifests a set of traits. "The phenotype of an individual organism is either its total physical appearance and constitution or a specific manifestation of a trait, such as size, eye color..." Not exactly. Wouldn't the following be more correct?
 * "The phenotype of an individual organism is its total physical appearance and constitution; a specific manifestation of a trait, such as size, eye color... is phenotypical, that is typical of the individual."--Wetman 14:24, 13 January 2007 (UTC)


 * This phenotype nonsense is just a means to help evolutionists formulate their endless http://en.wikipedia.org/wiki/Tautology_(rhetoric). All the article says is that :"...Animals have characteristics.." - which is a Truism. Of course they do, but that doesn't mean monkeys gave birth to humans, which is what evolutionists are trying to say. The words Genotype,Allele and Phenotype are undefined, you can associate any concept you want with it. And like I explained on the Tautology article the issue is the concept you have and not the symbol string itself such as phenotype. What is your concept with phenotype, what are evolutionists really to convince people of? —Preceding unsigned comment added by TongueSpeaker (talk • contribs) 11:54, 3 November 2008 (UTC)
 * I know a geneticist using the expressions "phenotype" etc. and who is a creationist (they're rare, but they exist). You're discussion really is not pertinent here. --Crusio (talk) 12:18, 3 November 2008 (UTC)

NPOV?
User 201.231.161.9 added the Neutrality Disputed flag but (as you can see) there's nothing here about the issue. Consider the dispute started I suppose! If I don't get some feedback I guess I'll delete the flag. I'm happy to leave it up if there is a dispute but it's a not really useful when there isn't. Shayno 16:48, 4 November 2006 (UTC) (Signed retrospectively!)
 * A familiar joke. With minimal effort they can make everyone scurry around. --Wetman 14:24, 13 January 2007 (UTC)

Definition
We need a more rigorous definition with a citation - does phenotype include something like dying one's hair (physical appearance) or does the trait have to be caused by one's genes? Richard001 04:01, 12 May 2007 (UTC)
 * How do you like the first section now - I even added a reference. The definition of phenotype doesn't have to be as complex as most of this page makes it out to be. You'll notice that "eye color" is not an example of a phenotype in this definition but "blue eyes" is. Dr d12 15:52, 12 May 2007 (UTC)
 * dying one's hair a color should be considered a phenotype, absolutely. Consider if a bird used natural pigments to change its feather colors - biologists would eat this up as a "complex behavioral phenotype." Debivort 16:54, 12 May 2007 (UTC)
 * LoL that is BRILLIANT Richard001/Debivort! I had just added the diagram from the Genotype article to clarify the relationship of Pheno/Genotype but maybe a good photo of a punk with a bright pink mohican would be a good addition too (off to source one!).  IMO the picture of bivalve shells is interesting but doesn't really help very much to clarify the difference, if you don't already understand it.  The phenotype seems a quite superficial thing (sic) compared to the genotype, having no greater significance that in growing a bonsai tree, or clipping a poodle, or growing a cubic watermelon. LookingGlass (talk) 04:48, 20 April 2013 (UTC)
 * Well, just to be clearer, a phenotype does need to be caused by the genome/epigenome. My bird example (from 2007) wasn't explicit, but I was imagining that the pigmenting behavior was under genetic control. As for phenotype being more or less important than genotype - it is the phenotype that determines fitness, and hence evolution. Hard not to consider it the most important. de Bivort 05:06, 20 April 2013 (UTC)
 * That is NOT being clearer Debivort but completely changing your stance! To be clear, you originally wrote: "dying one's hair a color should be considered a phenotype, absolutely.". To then suggest that phenotypes are "caused by the genome/epigenome" is to make the two terms synonymous or to create a tautology that renders the term phenotype redundant.  If all variations are "caused by the genome/epigenome" then that is the end of the story.  Dying one's hair is only "caused by the genome/epigenome" if you adopt a strict deterministic philosophy, in which case nothing is not "caused by the genome/epigenome".  However, if phenotype refers to the development of an organism in response to its environment, either prebirth in the form of a teratogenic change or post birth, both having no trans-generational impact on DNA, then neither results in an heditary trait and so does not have an evolutionary (DNA driven) impact such as you suggest but simply a possible impact on population. LookingGlass (talk) 07:58, 20 April 2013 (UTC)
 * A phenotype is the sum total of observable characteristics (traits) of an organism. Whether such traits are heritable or not is irrelevant. Dyed hair and blood groups are both observable characteristics. In fact, so are gene expression levels and I have seen research where genetic analyses of gene expression levels were carried out. --Randykitty (talk) 08:55, 20 April 2013 (UTC)
 * So, couldn't this be made clearer in the article? LookingGlass (talk) 10:57, 23 April 2013 (UTC)

Phenotype is not a trait
This page is at present a mixture of accurate and inaccurate parts. Most seriously, the intro section is wrong in saying that traits like blue eyes are phenotypes. They are not: they are aspects or parts of the phenotype. Neither is it true to suggest that characters need to be measureable; they need to be distinguishable.

So I'm going to try to at least make the intro more accurate. Macdonald-ross 17:10, 24 September 2007 (UTC)

Is the blood group really considered a phenotype? By the definition of this page it is very misleading - please change this example or augment the definitionLimaye (talk) 19:44, 24 February 2008 (UTC)
 * Could you elaborate further? GlobeGores (talk page | user page) 15:59, 8 March 2008 (UTC)


 * What do you mean? How is it not a trait? https://doi.org/10.1079/9781780642215.0598 Chamaemelum (talk) 19:09, 15 June 2023 (UTC)

genotype + environment → phenotype
genotype + environment → phenotype This formula can easily be understood as

genotype + environment = phenotype

by the general reader despite of the arrow. Therefore it is misleading, so it should not be placed at all. What does it contribute to the knowledge, except misunderstanding?--Wickey-nl (talk) 19:50, 1 May 2008 (UTC)

Are humans magically free from phenotypes?
Just curious. 184.96.230.182 (talk) 02:10, 24 November 2011 (UTC)
 * The lead refers to "organisms". Last I heard, that included humans. --Crusio (talk) 02:15, 24 November 2011 (UTC)

Thalidomide
I find the difference between teratogentic and mutagenic properties confusing. As far as I understand it, in the case of thalidomide for instance, the DNA of the embryo is affected causing birth defects which persist in the affected individual. It seems then, that while the original "starting" genotype might be the same as at the moment of conception, it is altered/maladapted/corrupted by the drug prior to birth. The "altered genotype" at birth would appear therefore to be different to the one at the moment of conception, so while in some hypothetical manner two children could be born with the identical genotype at conception their genomes might be different at birth. However it appears from the case of Thalidomide that this revised/deformed genome would not be hereditary, or its deformation would not be. Could someone clarify how a pre-birth phenotype change via the DNA is possible without it being a genetic change that becomes hereditary ie mutagenic? I might accept more easily, that as there is no evidence of second generation defects (yet?), there is no mutagenic affect if the mechanism could be clarified by which mutagenic action, ie the effect of a substance on the DNA of a cell and therefore of its replication, comes to be isolated from the formation of gametes and therefore becomes non-hereditary. Can anyone clarify? Is it that the teratogenic affect of thalidomide does not affect the gametes but rather specific cells in the embryo (which are not stem cells?)? LookingGlass (talk) 05:53, 20 April 2013 (UTC)


 * Oops, I think this paper answers my question: [Committee on Mutagenicity of Chemicals in Food, Consumer].  Might the article benefit from adding something about this? LookingGlass (talk) 06:03, 20 April 2013 (UTC)

Does anyone consider learned behavior to be a phenotype?
I suppose there are cases wherea behavior is a phenotype (FAPs, reflex), but is a learned behavior a phenotype? Mrdthree (talk) 15:37, 17 May 2014 (UTC)
 * Anything that can be measured is a phenotype. Different inbred strains of mice show vastly different capacities for learning and memory, for example, and many genetic analyses are done trying to uncover the genetic bases of those differences. Geneticists do genetic analyses of basically everything, including, for example, political preference and tendency to have a divorce. --Randykitty (talk) 17:29, 17 May 2014 (UTC)
 * I think that gets more into the idea of nature versus nurture. Although genetics can effect an organisms ability to learn, I think from genetics people are more inclined to certain behavior. There are definitely genetics that make you more likely to get angry or to effect your intelegence, but I don't think it would be considered a phenotype. If we stick with the definition of phenotype described in the rest of the talk page, then it is how your genes are expressed and effected by the environment. Like if your mom has anger issues and your dad doesn't, it is not inherited the same way as a physical disease.  Certain behaviors don't have a proven genetic element.  It is much more environmental.  I would say learned behavior is more nuture than nature, but a link to another page about nature versus nurture or learned behavior and genetics could be useful. --Mjb15f (talk) 13:07, 24 March 2017 (UTC)

Definition of Phenotype
The definition of phenotype as "the composite of an organism's observable characteristics or traits" is very unhelpful. This definition would seem to imply that it is impossible to specify a phenotype because there is no way you can know _all_ of an organisms observable traits. It would also seem to imply that there are as many phenotypes in a species as there are individuals within that species. Another brief section of the article talks about the difficulty in defining phenotype, and I think that section needs to be considerably expanded. In fact, based on my unsuccessful attempts at finding a useful and consistent definition of phenotype somewhere on the internet, and my discovery of this youtube video: https://www.youtube.com/watch?v=zdI2rtzGgEA, I think that if this article were to do the concept justice, the section on 'problems with definition' would have to cover around 80% or more of the article. In any case, the best way to start would be to go through the article and drop any definition that clearly *could not* be a useful definition of phenotype, starting with the definition found at the beginning of the article. In its current state, I don't think a layperson can really develop a useful notion of the concept of phenotype from this article. Comiscuous (talk) 00:08, 4 June 2015 (UTC)
 * I don't see a problem with the definition in the lead, which is the correct definition of phenotype. --Randykitty (talk) 08:34, 4 June 2015 (UTC)

Assessment comment
Substituted at 02:49, 30 April 2016 (UTC)

Phenotype and Race
At least one article related to race – "Race (human categorization)" – refers to the term phenotype to "denote genetically differentiated human populations defined by phenotype", BUT the article here does not mention the word "race" at all. If this is an appropriate use of the word, it should be added here with citations, especially as the word "race" has its own difficulties. The word "race" is also distinguished from the word "ethnic", in one or more articles on Wikipedia. The article here called "Ethnic group" may be helpful to consult with before adding the this article here, to be hopefully added by someone who understands the nuances of the science AND the cultural aspects, along with the sensibilities of objectivity and how the word is used in various countries that speak English as their main language. Misty MH (talk) 00:34, 17 February 2017 (UTC)
 * Discussion of race or species or other taxonomic groupings does not belong here. Phenotype ≠ genetic differentiation. "Genetically differentiated human populations defined by phenotype" means that although the populations are genetically different from one another, people assume that phenotypic differences represent those genetic differences, when in fact there is not necessarily a direct correspondence. Discussion of that belongs at Race (human categorization), not here. Sminthopsis84 (talk) 15:25, 22 February 2017 (UTC)

Phenotype and Dominance
I'm not sure if this would belong here or not, but if not there should at least be a link. Phenotype for many characteristics is determined by dominant and recessive genes. Since environment is mentioned as something that determines phenotype, I feel like inheritance should to. A possible heading could be "Genetic Influences On Phenotype" where dominant, recessive, autosomal and sexlinked can all be briefly explained. Then, they can be told how they effect which traits are shown in the organism. Even if inheritance is not explained, a link to inheritance could be added, and then how this effects phenotype could still be explained on this page. What do you guys think? --Mjb15f (talk) 13:18, 24 March 2017 (UTC)


 * I think alles is what you're talking about so some alleles are are marked what you would call marked so they can't change no matter what they have a marker and when another protein hits it, it hits that marker and it bounces off it can't it can't do anything to that that Gene or that allele so but then there's other Genes and they allow that it's not sex specific so going to be like the color of your eyes let's say it can be blue or brown depending on the parents it's not it's not really X Y dependent. The other alleles or genes or RnA I believe could DNA like a penis or a vagina the shape size of a penis or a vagina is going to be specific to the male or female X to Y chromosome. So the shape of the female vaginas not going to be affected by the male's penis Gene you see what I'm saying that's your phenotype. 209.171.85.217 (talk) 12:05, 13 June 2023 (UTC)

Language
Is there a phenotype system for human faces, and what kind of language terms does it use? -Inowen (nlfte) 03:33, 15 October 2018 (UTC)


 * Well, police photofit systems give them a means of describing faces, but that's way too specialized for this article, for which humans are at best a subtopic, human faces a subsubtopic, and languages for such a subsubsubtopic, if anything. Chiswick Chap (talk) 04:17, 15 October 2018 (UTC)
 * Humans are also a macrotopic because of being a superspecies. The next species down can't even read Wikipedia. Some insight into human phenotype systems would be great.-Inowen (nlfte) 19:02, 15 October 2018 (UTC)
 * Nope. You might have more of a case at the Human phenotype article, now called Human physical appearance. Chiswick Chap (talk) 20:14, 15 October 2018 (UTC)
 * Will look into it. Does the pro phenotyping software have article(s)? -Inowen (nlfte) 00:16, 17 October 2018 (UTC)

Male vs female phenotype
I'm going to go with breeding dogs since its's easiest. So your genotype is Saint Bernard let's say you're breeding St Bernard dogs I have to do is have two Saint Bernards you got your genotype now. Now phenotype X and Y chromosomes say you want a male dog like your old male dog so you're scrutinizing the male dog maybe you wanted the snout a bit longer like your old dog the tail of it shorter or big paws you're scrutinizing your male cuz you want a new male, or vice versa if you want a female you're scrutinizing the female you want a bit thicker cuz she she whatever or are you're looking for a little black patch on the back or whatever so you got to see have three litters and you have 20 puppies now you got one that's identical to your genotypes obviously there and you see one that looks just like your female that you want so you pick her out now you have your phenotype. Now the hardest part now is environment because it's it's a lot it's very environmental right if you try to treat it just like your old dog and keep the conditions just the same so that she got your old dog back but that's very difficult because you could leave her alone and you can go out with your wife to the movies or something and someone kicks your dog and ass or your kid hits it in the head with a bat changes its temperament right so now you're back to square one and you got to try to find another one and it could take you forever but but the phenotype I think is more in the male the female or X Y chromosome however not all traits you might be female in your female nowadays it alot to research and figure out less breeding involved. I could be wrong but I think it's more than a male or female so if you want the male you're scrutinizing the male for the snout the tail of the paws the colorings if you want the female or scrutinizing the females but basically you just breed to the same breed and that's your genotype and then your phenotype is like a longer tail smaller tail longer smaller snout one black spot. Or one brown and I want blue eye whatever your old dog had that's that's what you're looking for in your phenotype and your sex. I could be wrong but as soon as I hear pheno phenotype phenotype that just screams sex to me that screams female male just basic language man you know I just jumps right out at me I can feel it in like in me I'm thinking my blood bro people talking that s*** for 10,000 years now. It's like milk you know what I mean people in Vietnam in North Korea they're lactose intolerant people from where I'm from we die without that s*** I'll have to kill you if I can't get my milk you know what I mean. 209.171.85.217 (talk) 12:02, 13 June 2023 (UTC)

Proposed merge of Phenome into Phenotype
very wide overlap. fgnievinski (talk) 17:45, 29 June 2023 (UTC)


 * Support. Agree. "Phenome" is not a well-defined concept in contrast to "phenotype". --Randykitty (talk) 07:48, 30 June 2023 (UTC)
 * ✅ Klbrain (talk) 18:40, 22 July 2023 (UTC)