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8 votes
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Do stem cells have no epigenome?

So there are a couple of things to bear in mind. pluripotent does not mean that all genes are active. It means that the stem cells have the ability to form different cell types. However, it still ...
Jei Diwakar's user avatar
7 votes
Accepted

Is there a genomic code for nucleosome positioning?

The genome is the complete set of DNA in an organism, including genes and non-gene sequences of base pairs (bp).1 Each codon of three base pairs in a DNA sequence specifies one of twenty different ...
Dalton Bentley's user avatar
4 votes
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Spermatogenesis in humans - timing of phases and chromatin modifications

Spermatogenesis (Beginning to end): 64 +- 8 days (range 42 to 76) There is considerable individual variation. This includes time in epididymis. Amann 2008 argue ...
Calen's user avatar
  • 191
4 votes

How does geography affect morphological features of the human body

Geography does not typically affect the morphology of the human body. In certain special cases, there are physiological adaptations, the most obvious being tanning and acclimatization to high altitude,...
jakebeal's user avatar
  • 6,987
4 votes

Are epigenetic modifications the most stable mechanisms for cell differentiation?

Epigenetic marks are reversible (you might be aware of induced pluripotent cells). Many animals can regenerate organs with high tissue complexity (such as a limb) and this involves de-differentiation ...
WYSIWYG's user avatar
  • 35.6k
4 votes

Can epigenetics have positive impact on the genes are development?

First, let me qualify the idea of "problematic" epigenetic modifications by saying that the impact of a modification on an organism is often dependent on the environment. That is to say that outcome ...
acvill's user avatar
  • 8,296
4 votes
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DNA methylation and the validity of the definition of epigenetics

A methylated nucleotide is the same nucleotide, for the purposes of base-pairing events. The methylated base will be paired with its Watson-Crick opposite after replication, for instance (and ...
Alex Reynolds's user avatar
4 votes

Role of epigenetics in evolution and transmission of defects caused by drugs

Generally speaking, epigenetic modifications are not inherited as they are reset during embryogenesis. However, subsequent epigenetic modifications can be acquired during the period of pregnancy, ...
KaPy3141's user avatar
  • 1,597
4 votes
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Can instincts disappear after a long period of non-usefulness?

If it is like any other genetic trait, it will only be weeded out if there exists selective pressure that makes it counter-productive. Merely not being useful is not necessarily sufficient. Though I ...
DKNguyen's user avatar
  • 920
3 votes
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Can supplements affect DNA? (Could 10,000% Methylcobalamin affect MTHFR genotype)

What the DNAfit test does is analyse some of your genes for common variants (called SNPs - single nucleotide polymorphisms). These are hard-written in your genetic code, they won't ever change (you ...
Nicolai's user avatar
  • 4,391
3 votes
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Is protein production doubled if you have homozygous dominant genes as opposed to heterozygous genes?

Dominance is defined based on the phenotype Dominance is defined based on a phenotype of interest. Pick a phenotype, say coat color for example. If genotypes AA ...
Remi.b's user avatar
  • 68.1k
3 votes

Is there any biological basis for the emphasis on the value of the firstborn son?

There are lots of cases reported now that suggest that overall the firstborn child is usually more intelligent. The articles supporting this are based on behavioural and economic study though, so the ...
Joe Healey's user avatar
  • 1,301
3 votes
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How does CpG island methylation lead to gene silencing?

CG methylation has long been associated with gene silencing due to the generally negative correlation between gene promoter methylation and transcription levels. When CG methylation occurs in the ...
dblyons's user avatar
  • 382
3 votes

Are enhancers and silencers considered as epigenetic modifications?

No. Epigenetic information is (by definition) NOT included in the nucleotide sequence, but affects genetic expression. Enhancers/silencers are themselves nucleotide sequences, and therefore not ...
Diio's user avatar
  • 154
3 votes
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Does the bending of a tree's trunk in the wind stimulate and strengthen root growth?

In tree growth there is principle called The axiom of universal stress whereby the growth is in such a way as to equalise the stress across the whole of its structure. The roots, the stem and the ...
Martin Hügi's user avatar
3 votes

Studying the epigenetic variability, can I use SNPs?

Starting from what appears to be your main question: Can I use SNPs associated with a gene's higher expression to compute the likelihood of that gene being expressed in the brain region? I would ...
Nicolai's user avatar
  • 4,391
3 votes

Why do I get cytosine to guanine/adenine transitions in bisulphite treated sequences?

I quickly aligned your sequences, and as far as I can tell, the answer is that your "consensus" sequence is a poor match for the 3 other sequences: ...
Maximilian Press's user avatar
2 votes

Do findings on promoter methylation of the serotonin transporter gene and amygdala activity contradict the established view of serotonergic function?

I don't think there is an obvious contradiction here. (1) Mapping neuronal function to the perception of threat (or emotions in general) is often advertised as well-understood, but in fact it is not. ...
TheChymera's user avatar
  • 1,336
2 votes

How to confirm pure-breeding parents

If they are "pure-breeding", that means that they are homozygous. If they were heterozygous, the offspring would not all have the same color as the parents. But tree-breeding" means they all do.
swbarnes2's user avatar
  • 5,230
2 votes
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Is post-transcriptional regulation of gene expression an epigenetic process?

miRNAs and other post-transcriptional regulators are very well "genetic". They are encoded by genetic elements, are expressed and are affected by mutations. Just because this mode of regulation was ...
WYSIWYG's user avatar
  • 35.6k
2 votes
Accepted

Can a gene-expression or epigenetic 'user-history' be found in the body?

Main question Does the body store a history of these expressions? Do the chromosomes (or some other part) of an older organism store a 'user-history' of which genes where previously activated ...
WYSIWYG's user avatar
  • 35.6k
2 votes

Can a gene-expression or epigenetic 'user-history' be found in the body?

First Paragraph - let's debunk what was poorly phrased Many sentences you wrote are quite misleading. You should have a look at an introduction to molecular genetic to have a better understanding ...
Remi.b's user avatar
  • 68.1k
2 votes

Is there natural occurrence of induced pluripotency / expression of Yamanaka factors and what is the evolutionary explanation of that?

Regeneration of complex tissues like limbs is known in many animals. Salamander has been used as a model for limb regeneration. During regeneration, the cells at the amputation site de-differentiate ...
WYSIWYG's user avatar
  • 35.6k
2 votes

Is there natural occurrence of induced pluripotency / expression of Yamanaka factors and what is the evolutionary explanation of that?

What is a pluripotent stem cell? A pluripotent stem cell is a cell that can differentiate into any of the major tissue categories. Every animal exists as a collection of pluripotent stem cells at an ...
Bryan Krause's user avatar
  • 45.9k
2 votes
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Do epigenetics determine the proteins a cell produces and therefore it's function?

Short answer: Yes, epigenetics play a role in determining gene expression, therefore protein expression and function. Lifestyle factors like diet, smoking, alcohol consumption, and stress can change ...
aeffenberger's user avatar
2 votes

Semantics Question: epigenetic mark on a person's DNA?

It all depends on your definition of epigenetic. The one assumed by @ning, that appears to fit the case, is that cited in the Wikipedia article on the topic is: “Epigenetics is the study of ...
David's user avatar
  • 26k
2 votes
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Semantics Question: epigenetic mark on a person's DNA?

We may restrict your definition of epigenetics as heritable changes in an organism's phenotype that occur without a change in the sequence of DNA bases. That is, changes to the DNA molecule itself is ...
ning's user avatar
  • 377
2 votes

How can epigenetic changes be erased if they are inherited?

I have done a presentation in epigenetics and the main topic was imprinting. This paper will answer all your questions https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3941233/ I am adding some glimpses ...
Sarannya E's user avatar
2 votes
Accepted

"50% of the variance in antisocial phenotypes is the result of genetic factors" means what?

In a population the phenotypic variance can be caused by several underlying variance including the variance in the environment and the genetic variance (among others). The fraction of the phenotypic ...
Remi.b's user avatar
  • 68.1k
2 votes

Evidence against aging caused by loss of information in genome and epigenome in humans?

By loss of genome, I think he is referring to the shortening of telomeres. This study compares the length of telomeres of human epidermal cells. The authors report that over time, the telomeres do ...
Roni Saiba's user avatar

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