Questions tagged [dna]
Deoxyribonucleic acid (DNA) is the carrier of genetic information, including for all known living organisms. The only known exceptions are RNA viruses.
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Are there beneficial genetic mutations identified by consumer DNA genotyping?
I'm looking at services like 23andme, and see that they identify a wide variety of genetic-based risks, like predisposition to diseases, hair loss, cancer, etc.
Are there a more "positive" DNA ...
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Transcription factor binding site located in intron
I have noticed that some TF binding sites are located in the introns of the genes.
I am puzzled about whether the TF only binds to DNA in the initiation stage of transcription and will detach during ...
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Is there a DNA test to identify dog mixes?
We adopted a dog at the age of two. Our vet said it was a mix of an Australian Shepherd and Border Collie, which we've told everyone. Based on markings, I think it's likely. I am wondering, however, ...
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Prenatal Marketing
This is for a short story idea.
Is it possible to modify the DNA of a child to make their metabolism more susceptible (physical response, addiction, etc) to a certain type of chemical i.e. a chemical ...
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Superposing DNA
I have a series of protein models with DNA docked. I now want to superpose the DNA on a reference DNA molecule and extract the translational distance applied and the rotation angle used.
I can ...
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What is the purpose of Y-shaped adapters in Illumina sequencing?
Y adapters different sequences to be annealed to the 5' and 3' ends of each molecule in a library.
The arms of the Y are unique, and the middle part, connected to the DNA fragment, is complementary.
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DNA replication Okazaki fragments
I understand multiple origin bubbles; DNA polymerase only synthesizes DNA from 5' to 3' and all that. But what I don't understand is why it has to be in fragments. Yes, DNA is anti parallel, and so ...
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can the face of a person be accurately predicted from DNA information? [duplicate]
http://blogs.smithsonianmag.com/artscience/2013/05/creepy-or-cool-portraits-derived-from-the-dna-in-hair-and-gum-found-in-public-places/?utm_source=plus.google.com&utm_medium=socialmedia&...
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BLAST DNA Sequences Reversed
I have been trying to learn some basic DNA sequencing techniques and have been using BLAST as a reference. I thought that I was starting to get it, but then I cam across this:
It looks like it's ...
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How do mutations come to be shared by all cells?
It's my understanding that various hazards can damage the DNA in our cells, causing mutations.
But whenever I picture this, I see the damage being done to one of our tissues (for example, our lungs ...
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Separating DNA Fragments by Gel Electrophoresis. Are all the strands for one size the same?
My apologies if my question is too basic, and please point me to a more appropriate forum. I am reading the textbook "Essential Cell Biology" by Alberts et al, and am consulting other sources as well....
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Tool for nucleotide alignment with all nucleotide codes (e.g. R, Y, W, S, etc.)?
I have a vector sequence and would like to find the following nucleotide sequence in it.
AASYWSRA
This query sequence uses several degenerate symbols, defined as:...
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Is episome a plasmid or a virus?
A plasmid is a small DNA molecule that is physically separate from, and can replicate independently of, chromosomal DNA within a cell.
In general, in eukaryotes, episomes are closed circular DNA ...
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Expanding the SETI initiative to seek intelligent data within DNA sequences?
I've recently read a couple articles dealing with long term data storage, and DNA was suggested as one of the prime candidates for long term storage of digital data additionally, there is this article ...
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Complexity in creating transgenic animals (e.g., mice)
Many papers I have seen describing transgenic rodent models (and presumably applicable to other model organisms) involve the knock-in, or modification to, a single gene, possibly two genes. With ...
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Is there a way to measure the amount of bytes that are possible to encode in a DNA molecule?
When I saw a DNA molecule for the first time, it kinda reminded me of a hard drive. It consists of slots and there are some possible combinations for each slot; in the hard drive these possible ...
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Do individual (free) nucleotides base-pair with other free nucleotides?
I had a student ask me about this and my google-fu let me down. He asked if individual nucleotides (not in a nucleic acid) base-pair with their complementary nucleotides, essentially forming many ...
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High sequence similarity but start codon isn't methionine
I have noticed in a particular genome sequence of a prokaryote that various regions in a sequence share similarity which is high(>80%) with known proteins. However, the start is not a methionine. Is ...
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How much can be said about behaviour (future) based on bloodgroup?
My bloodgroup for example is A+. How much information is knowing my bloodgroup? How much information can be known from a blood sample? I expect you to be able to clone if known a complete DNA sequence ...
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Can IVF decrease the probability of trisomy in the fetuses of older mothers?
Is trisomy mostly due to complications with fertilization?
If so, does in vitro fertilization reduce the probability of trisomy for the fetuses of older mothers?
If not, can zygotes be screened ...
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How is instinctual information encoded?
If instincts are passed on through genetics, how is that information encoded in DNA?
For example, spiders instinctively know how to spin webs. Does that imply that the algorithm for web spinning is ...
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How does a thymidine block halt DNA synthesis?
The best I've been able to find is that there's a feedback mechanism, but what is this feedback, and how does the mechanism work? If it's just that the concentration of thymidine is too high, why won'...
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Can forensic DNA analysis be used to generate a visual approximation of a suspect?
In light of the current US supreme court case, I'm curious if enough information can be teased out of a DNA sample to get a "reasonable" approximation of the suspect (never mind the legality). I ...
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Why re-label the strand ends in 3' DNA labelling?
I have a problem with a molecular biology question; I don’t understand how DNA 3’ labelling works.
I took a diagram from my lesson and tried to understand with it; this is what I understood.
If I’m ...
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What are the limitations of commercial-grade DNA genotyping compared to full sequencing?
I've heard about services like 23andme, which offer genetic testing to the general public. As a person who knows very little about genetics, I'm interested in the subject and would like to know what ...
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How does Topoisomerase II inhibition affect cancer cells?
Topoisomerase II poisons represent some of the most important and
widely prescribed anticancer drugs currently in clinical use. These
drugs encompass a diverse group of natural and synthetic ...
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Studying changes in DNA for causes of cancer
First of all let me say that I'm not into Biology myself... but I have a question for those of you who are.
From what I've read, cancer is caused by 'faulty' DNA that behaves abnormally. Mutations ...
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How does formaldehyde cause protein-DNA crosslinking?
How does formaldehyde cause protein-DNA crosslinking? I would guess it's because the strongly polar water molecule interacts strongly with polar residues on a protein-DNA complex, and adding a less ...
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How to find Exons in mRNA Computationally
I'm having trouble finding a method to find exons in the original DNA sequence used to create the mRNA, even given the sequence of the mRNA, as I cannot find a way to reliably identify the beginning ...
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Why are 3 nucleotides used as codons for amino-acid mapping in DNA?
DNA is made of 4 unique nucleotides. When coding for a protein, a sequence of 3 nucleotides is used to code for each amino acid. Why are codons 3 nucleotides in length?
A related question can be ...
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What is the fibre axis in the Watson and Crick paper?
I was reading Watson and Crick’s original article on DNA structure in Nature 171, 737–738 (1953). The accompanying diagram (shown below) has something called the “fibre axis” going through the DNA. ...
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Papers linking telomeres and aging [closed]
I'm currently writing a piece of work about telomeres and aging, and wondered if you could share some good papers you've either read or know of.
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Simulating Cell differentiation
I'm a computer programmer deeply interested in Biology.
I wish to write a computer simulation for cell differentiation. I understand there will be seemingly impossible challenges in doing this. But ...
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How do multiple replication forks function without 'colliding', and what is the benefit of this method?
I'm currently reading a little about DNA replication, and have come accross the following statement;
Replication starts from a fixed point and is bi-directional ... In Eukaryotes, there are ...
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What kind of event would cause the current Mitochondrial Eve to be replaced by a new one?
Apparently all living humans are matrilineal descendants of a single woman who lived 200.000 years ago. She is called Mitochondrial Eve.
But at the time she lived there was a different matrilineal ...
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Difference between mice and rats
What is the actual biological difference between mice and rats? Are they actually the same thing with two different names depending on appearance (are they all mice for instance and we call the larger ...
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mutant down but not out
I am interested in a gene which is null lethal but I need to temporary induce diminished capacity. If a cell is homozygous is it possible to induce heterozygous phenotypes or a partial knockout from ...
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How are atoms in benzopyridines and benzopurines numbered?
I am well-aware of the numbering system used for the traditional bases, as seen below.
My question is how are the atoms in the size-expanded bases seen in xDNA and xRNA numbered?
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DNA as an acid? [duplicate]
Possible Duplicate:
Does DNA react in all of the ways most other acids do?
Even if DNA is made up of nucleotide bases, it is said to be an acid. Why is this?
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What is the oldest example of DNA identified?
What is the oldest sample of genetic material (presumably DNA) identified? What are the prospects of pushing back much further into the geologic record?
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Does DNA react in all of the ways most other acids do?
As I understand it from my basic chemistry, there are some fundamental reactions that exist between any acid and other substances for example acid-base reactions that form a salt, and the existence of ...
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Translate DNA to Protein
Assuming the sequence shown is read left to right, what is the sequence of the protein produced?
sequence: 5’-ATGTACTTCCATCTGGAATAG-3’
MY ATTEMPT: I know RNA is synthesized 5 to 3. This is ...
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Can DNA act as a translation substrate?
I get conflicting answers. One would think if it was true, it would be rather seminal and widely known.
There are papers from Khorana[1], Holland[2], and Bretscher[3] (late 60s) that suggest that it ...
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How are DNA polymerase error rates measured?
It is well known that the first DNA polymerase, Taq, is quite error prone. Newer generation commercial enzymes that have either been isolated from different thermophile species or have been improved ...
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How to learn DNA Origami
Can you tell me is there any good softwares and tutorials which can be used to learn DNA Origami. I am new to this and want to learn from basics.
Advance thanks for your help
edited: INSILICO
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What distinguishes "coding" from "noncoding" DNA?
I've been reading a bit about "junk DNA" and how much of our genome consists of this "non coding DNA" in comparison to "coding DNA".
I'm just an interested layperson but I thought all combinations of ...
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Is there an advantage to linear chromosomes?
The DNA copying enzymes have a hard time working to the end of a chromosome. For circular chromosomes this is not a problem, since there is not a sharp 'end'. However, for a linear chromosome, without ...
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How does "inheritance of methylation" of DNA and/or histones work?
What are the current models/ideas describing the mechanisms explaining inheritance of methylation on DNA resp. histone level?
Is there evidance of this "setup" information being really duplicated/...
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Evolutionarily speaking, why do humans have 46 chromosomes
In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Monkeys, chimpanzees, and Apes have 24 pairs (twenty-four pairs), for a total of 48.
What caused humans to have 46?
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What would need to be discovered to prove there is extraterrestrial life?
Curiosity is on the Martian surface and is equipped with a slew of laboratory equipment. What would Curiosity need to discover to prove there is or has been life on Mars? Would it have to find DNA (or ...
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