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Regarding the meio/majo or micro/macro suggestion: Micro and macro-chromosomes are terms already used in species such as chicken whose genomes combine very small and big chromosomes Although this is more the exception than the rule, bear in mind that sometimes the Y chromosome is bigger than the X chromosome (e.g. in S. latifolia) As for the initial ...


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I think you can safely use the terms heterogametic (Y/W) and homogametic (X/Z) chromosomes, meaning that a heterogametic chromosome is the chromosome which makes one of the sexes heterogametic (i.e. defines the difference between the two types of gametes of the respective sex). These terms applied to chomosomes do have some usage in the literature, e.g. in ...


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Your markers are probably fine, especially because you keep seeing the same allele in multiple individuals. Dinucleotide repeats do not always copy perfectly. More likely, remember that the primers you use to amplify your microsatellites bind outside of the actual repeat region. You could have an insertion/deletion in the region between the primers and the ...


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"Monosomy for the X chromosome in humans creates a genetic Achilles' heel for nature to deal with." The article I quoted1 tackles this issue. It's from the turn of the century, though, so quite old in sequencing/genetic terms, but the science is still sound as far as I can tell. Here's the money quote: Hence, the X chromosome appears to have a lower ...


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Parts of your general idea are correct, others need some refinement. To skip ahead to the conclusion: I'm going to recommend that you read up about linkage disequilibrium. Everything else is background information that will hopefully help you understand why linkage disequilibrium is what I think you're looking for. Background: Meiosis Basics Firstly, in ...


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some number of interstices (spaces between successive loci) get picked and each chromosome gets broken at each interstice. That number is usually around 1. It's not common to have a lot more than that per chromosome. It also seems clear that all interstices are equally likely to get picked. No, there certainly are "hot spots" that are more ...


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In response to Oreotrephes answer I see fit to point that the selective pressure against an insect being pink and a manual being pink is quite different but could also be the same. Take our species for example: the first humans were dark skinned thought to be as a genetic advantage to our then dark forrest and tree land environment. As we evolved into a ...


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I realize this question is about yeast, but I'm afraid that people may try to expand the answer to all systems, and beta galactosidase is not good for all systems, particularly for animal studies. I've seen too many gene therapy papers try to get away with using it. Beta galactosidase is not a good reporter gene for in vivo gene delivery studies. There is ...


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Pink individuals of the katydid species Amblycorypha oblongifolia are a relatively uncommon but natural phenomenon with a long history of research. It looks from popular press accounts (Science Friday, Scientific American) that the pink coloration may be caused by a dominant allele, and is only rare because of a high selection pressure against pink ...


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Plus and minus describe what is happening in a specific locus in the genome. When a + sign is shown, the locus contains the natural, fully working gene (wild type). When a - is shown, it means that by natural mutation or lab manipulation, cells lack that natural gene, or make a negligible amount of it, or make a broken variant etc. These cells are diplod, ...


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I do not think there is a reproductive advantage in gray hair - it's the other way around: Normal colored hair has a reproductive advantage. But it also has a cost in terms of substances needed to build it. I make the assumption here that grey hair - which is often also more sparse - has a lower cost in terms of material. I think we are investing the ...


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Presumably this means that at least some grey haired humans have noticeable reproductive advantage, or maybe they had it in the recent past. No it doesn't. Natural selection is not that strong, it doesn't optimize every single possible physical trait towards maximum reproducing. And as others have mentioned, having lots of grey hair usually ...


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Here is what the data says. UK government must have had some scientific evidence when it settled on a 10 variable-length sections of genome for their database, SGM+. In one such variable sections, some people have 10 repeats of CTTT, others have 11, others have 12 etc. The largest of those fragments, at its maximum length, are about 350 base pairs. The US ...


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The new mexico whiptail reproduces purely through parthenogenesis. The species itself originates as a hybrid of two other species of whiptail, but the hybridization can't make fertile males. The females can reproduce through parthenogenesis so that's how the species continues to exist. So 100% of the genome is passed mother to daughter for many generations, ...


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When designing PCR primers we typically use a minimum length of 20 bases, because the probability of a sequence of N bases appearing by random is $\frac{1}{4^N}$, and $\frac{1}{4^{20}}$ is about 9x$10^{-13}$, or about 1 in a trillion. Since the human genome is a little over 3 billion bases long, a 20 base sequence should appear only once. However, most of an ...


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Is there any species (not just mammals) where most, or even all, of the genome is inherited in a sex-specific trajectory? If all the genome is passed on by only one sex, then the other sex will necessarily disappear (in absence of social reasons) (and the species may go extinct if the presence of this other sex is necessary). However some cases such as ...


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In birds and reptiles females are the heterogametic sex with allosome configuration ZW. However it has been reported that a homogametic WW female boa was born by parthenogenesis. So it means that although W is shorter than Z, it can still support life. So I guess that ZW system in general exchanges more sex-limited genetic material than XY system. Platypus ...


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A tumor suppressor is an essential gene that regulates the cell cycle at different checkpoints. If one allele is lost due to a mutation then the function of that gene can be carried out by the other allele (There might be a less expression of that gene because of copy number reduction but it is not necessary in all cases- cases where there are feedback ...


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Suggestions: Evolutionary Genetics : Concepts and Case Studies: Concepts and Case Studies Edited by Lexington Charles W. Fox Department of Entomology University of Kentucky, Faculty of Life Sciences University of Manchester Jason B. Wolf Lecturer The mathematical theory of selection, recombination, and mutation by R B├╝rger (as suggested by @GriffinEvo in ...


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These equations describe how the haplotype frequencies will change over time due to a combination of recombination and natural selection. Before I proceed, I need to change your four $\delta X_i$ formulas above. Lewontin and Kojima (1960) writes the equations as: $$\Delta X_i = \frac{X_i(w_i - \bar w) \pm Drw_{14}}{\bar w}$$ where the minus sign is used ...


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RNA was almost certainly the first genetic molecule of inheritance. However, the single-stranded nature of RNA is not particularly stable and thus would not be reliable for the long-term storage of genetic information necessary for reproduction (and ultimately evolution). The necessary stability is provided by DNA. The question becomes, how did DNA evolve ...


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Imagine you want to produce a widget. You have thousands of worker, but only one blueprint. Each worker needs the blueprint to build a widget (they're really forgetful and can't build from memory). So only one worker at a time can build your widgets. What you would do is to create copies of your blueprint and distribute them to your workers. That way ...


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OK, I found this on Wikipedia. I probably should have checked there first! DNA has three primary attributes that allow it to be far better than RNA at encoding genetic information. First, it is normally double-stranded, so that there are a minimum of two copies of the information encoding each gene in every cell. Second, DNA has a much greater ...


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As the previous answers clarify, all organisms have heritable traits that may be manipulated through selective breeding. It is the pragmatics that can be prohibitively challenging. From an (zoo)archaeological point of view, few animals have actually been domesticated, and only recently in our species' history. The dog is an unusual case, perhaps domesticated ...


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See these two papers: Early Loss of Xist RNA Expression and Inactive X Chromosome Associated Chromatin Modification in Developing Primordial Germ Cells X Chromosome Reactivation Initiates in Nascent Primordial Germ Cells in Mice Basically it happens just before the meiosis.


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In the linked paper, the authors discuss this as sex-based gene expression that evolved by sex-specific selection. The expression is not limited to one sex (which are sex-limited genes). Sex-biased genes are expressed by both sexes, but differently between sexes.


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Is SS clearly different from Natural Selection (NS)? Is SS nested within NS or are NS and SS two different and (anti- or not) parallel processes? Darwin, in The Descent of Man, and Selection in Relation to Sex defined sexual selection as a type of selection that "depends on the advantage which certain individuals have over other individuals of the ...



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