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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Basic Amino Acid Residue Binding Mechanism to DNA

I understand that many protein DNA binding domains bind to DNA via basic residues such as Arginine and Lysine. But what is the mechanism used to bind to DNA and where on the DNA would these residues ...
7
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4answers
153 views

How can I produce milligram quantities of an isotope-labeled DNA oligomer?

I'd like to produce a specific DNA sequence on a milligram-scale and 13C15N-label it. The sequence is around 35 nucleotides long, so chemical synthesis is out due to the exorbitant costs. I'm also ...
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0answers
22 views

3' or 5' DNA capping protein

Does anyone know of a protein/molecule that can be attached to one end of the DNAs temporarily ? eg. i would like to only to allow one strand of DNA be ligated to another DNA molecule to either it's ...
0
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1answer
191 views

What is the difference between SNP and STR?

I thought that these were just different format of the same data. But it seems there isn't a way to convert SNP (single nucleotide polymorphism) data to STR (short tandem repeat) data. Am I right? ...
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1answer
94 views

Can two denatured DNA strands reassociate?

What matter if I increase the temperature to 95°C. So double-strand DNA denatured into two ssDNA, and then I decrease the temperature to room temperature. Are they able to reassociate after ...
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1answer
48 views

Why use DNA polymerase in making cDNA?

RT is capable of synthesizing a complementary dna strand ( as in HIV life cycle.) Then why is DNA pol used when cDNA (synthesizing the second strand of it ) has to be synthesized from mRNA ( For eg.to ...
4
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1answer
75 views

Stability of helical strands of DNA?

The DNA molecules contain phosphate groups involved in $3'\rightarrow 5'$phosphodiester linkages. These groups, in the bonded state with deoxyribose, contain 1 negative charges ($\ce{3'-PO4^{-}-5'}$). ...
2
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2answers
524 views

Difference between CDS and cDNA

What is the difference between Coding Sequences (CDS) and cDNA? Are Coding sequences the sequences that is transcribed to mRNA and cDNA in contrast DNA obtained by reverse polymerization of matured ...
3
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3answers
130 views

How to learn molecular biology through pubmed research articles?

Instead of using a textbook, is there an alternative curriculum, that simply lists a set of pubmed research articles for each topic covered in a typical undergrad molecular biology course? I am ...
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2answers
150 views

How much natural genetic variation is there between bacteria of the same species?

There are lots of questions about how and why there is genetic variation between organisms of the same species, but I haven't been able to find a numerical value for the expected amount of genetic ...
8
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1answer
378 views

How many gigabytes of DNA are there on earth?

The human genome is about 770 MB, the C. elegans genome is about 100 MB, the yeast S. cerevisiae is about 12 MB. Different other genomes have been sequenced: how many GB of genomic DNA we have now? ...
4
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1answer
102 views

Microarray data and analysis tools

Microarray has various uses, and to analyse the data a main function classification is used. There are many methods used to classify the data but what are the best and most frequently used methods? ...
2
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1answer
111 views

How does electroporation mediated recombination work?

For yeast and other organisms, DNA can be readily taken up into the cell naturally or through membrane disruption. What does applying a voltage to cells do exactly that allows more recombination to ...
8
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2answers
117 views

What is the effective relatedness of inbreeding?

If a human inbreeds with a relative, how distant does the relative have to be before the homozygosity in the child is no higher than if the mate were randomly chosen from the global population?
6
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4answers
342 views

Does RNA polymerase move around DNA or does DNA rotate benath the polymerase?

I'm thinking of the human genome specfically, but more general answers are welcome. As RNA polymerase moves along the DNA helix it follows a single strand. The two DNA strands are unwound locally ...
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1answer
73 views

Do mitochondrial DNA have repair enzymes?

Mitochondria are considered endosymbionts originated from a prokaryote. So, do they have a DNA repair mechanism ?
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1answer
40 views

Reassociation of DNA

What is the order in which this DNA samples would would reassociate ? e.coli DNA plasmid DNA viral DNA satellite DNA DNA-RNA hybrid This is a homework question and I have not been given any ...
3
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1answer
340 views

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 ...
5
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2answers
88 views

There are linear and rotary molecular motors in the cells. Do any of them have a fixed or stable frequency or speed?

Are there any linear, rotary or oscillatory molecular motors in the cells which can have fixed frequeny and which can be used as a reference for elapsed time timer? This question is with relevence to ...
2
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0answers
78 views

What to do with a DNA sequencer? [closed]

My school is very fortunate to have a DNA sequencer, and I want to find an opportunity to learn how to use it. I'm currently taking AP Biology this year, and I hope to do an independent study in ...
5
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3answers
1k views

Do apes and humans share 99% of DNA or 99% of genes? What is the difference?

I made an answer on the Scifi.SE that can be read here. It is about how the characters in the story Jurassic Park might have gotten DNA for all the species shown. In my answer, I said this: Apes ...
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1answer
24 views

Genotoxic agent and their metabolic pathway

What are the mechanics (set of biochemical reactions) allowing a given genotoxic agent to modify the mutation rate at a given spot? to induce only a given type of mutation (from Gs to Cs for ...
4
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0answers
35 views

Is telomere shortening consistant over consecutive cell divisions from zygote to a differentiated cell?

Considering the complexity of embryogenesis, a temporal referance would be helpful to coordinate the developmental sequences during embryogenesis and fetal development which is to be completed within ...
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3answers
1k views

Does our DNA change during our lives?

As far as I know, DNA is the construction protocol of all organisms on Earth. Does it change when influenced by time and environment (physical laws)? As parents with schizophrenia are more likely to ...
2
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1answer
328 views

Difference between viral and human genetic material

I have heard that there is a difference between viral and human genetic material. What is that difference? If I take my cells and take DNA out of them and insert only a small part of it having a ...
5
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2answers
1k views

What conditions should I use for Gel Red staining?

What are the optimal staining conditions when using Gel Red? So far, since we have started using it, the gels ran in our lab have been of very poor quality. The bands are very blurred and often ...
2
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2answers
149 views

Basic text/notes on DNA structure (for non-biologists)

I am a mathematics grad student researching knot theory, and I've recently discovered that there is a connection between knot theory and DNA structure (if I understand correctly, when DNA strands ...
3
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1answer
541 views

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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2answers
65 views

Why can't we observe haplotypes directly?

I am completely a noob to biology and DNAs, but recently I am looking into EM-algorithm used in the case of re-constructing haplotypes from genotype data. I am just wondering what exactly in the ...
4
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1answer
129 views

Which organisms have introns?

From Wikipedia: For example, introns are extremely common within the nuclear genome of higher vertebrates (e.g. humans and mice), where protein-coding genes almost always contain multiple introns, ...
2
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1answer
120 views

Why are urban birds still scared of humans?

I understand that animals are naturally scared of humans because we basically slaughtered every living thing we found in our way for millennia. How long does it take for them to genetically 'forget' ...
3
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1answer
91 views

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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1answer
82 views

Do spouses begin to share genes over time?

I apologize if this hypothesis sounds strange by I was wondering if any research had been done on a phenomenon which I've seen and have corroborated with many other - the idea that over time spouses ...
3
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1answer
419 views

What happens when cells in your body run out of telomeres?

In my biology book I read about an experiment where the genes encoding telomerase were 'knocked out', but they could still live a normal life and no adverse effects were noticed until the 6th ...
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1answer
58 views

How do I figure out which of the valleys I came from?

I had my DNA tested by 23andme.com. They give me a very long string for my DNA. How do I determine which of the three Ethiopian valleys I descended from? I'm of European descent. ...
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1answer
48 views

How correlated are proximally related CpG sites in human DNA?

Cytosine residues in DNA that can be methylated (i.e. CpG sites) are likely to be in the same methylation state if they are geographically (proximally) close together. I can only find one paper that ...
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1answer
61 views

Complementarity of cDNA

Strictly speaking, what is the definition of cDNA? This confuses me, since usually it is said to refer to DNA that is complementary to mRNA. Is this correct? Is it restricted to mature mRNA? I ...
5
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2answers
522 views

How long is DNA stable in a freezer?

Inspired by the post about extracting pet DNA, how long would genomic DNA be stable for in a -20°C freezer? It is common practice to store DNA (double-stranded, plasmid) in a -20°C freezer in ...
3
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1answer
162 views

Can replication occur if DNA is methylated?

Can a methylated strand of DNA be replicated without removing methylation? Does it make any difference if the strand is methylated or not (during replication)?
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2answers
87 views

Can retroviral delivery systems “overwrite” genes?

As the question states, what are the limits of retroviral genetic delivery systems? Are they limited to adding additional gene sequences to a cell, or can they actually overwrite specified segments ...
0
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1answer
174 views

When can a virus modify DNA in every cell of a living organism?

I've recently heard about experiments with brain tissue, where a virus is introduced in a rats brain, causing a "glow when electric charge is present" protein to be created. This protein then helps to ...
3
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3answers
154 views

Is there variation of AT/CG ratio along species?

Chargaff's rules say that the number of Adenine of the number of Thymine in a genome are equal (nA=nT) and similarly nC=nG. This makes obvious sense knowing that C binds to G and A to T. But what ...
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1answer
145 views

How to deduce if RNA virus infection or DNA virus infection

Is there any general rule to say this must be RNA virus infection and the other one DNA virus infection? Example of a case: 5 children develop a bright red rash on the face and turns violet after a ...
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1answer
105 views

Suggestions for an experiment? [closed]

I would appreciate suggestions for my year-long AP Biology project. Such a project would consists of a standard experiment, to be done over the period of a year, so it would have >to be fairly ...
3
votes
1answer
375 views

What is DNA binding domain? It is not clear what the domain means

I am confused about the term DNA binding domain. Does it mean that there are some parts of the DNA that tends to coil up? Does it happen because some proteins tend to stick around that area? Also it ...
32
votes
4answers
2k views

Life without DNA?

I'm by no means an expert in the field, merely a curious visitor, but I've been thinking about this and Google isn't of much help. Do we know of any lifeforms that don't have the conventional ...
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4answers
144 views

Is there any other function of DNA?

We all know that DNA acts as a genetic molecule. Does DNA have any other function in the cell other than being a genetic material and carrier of information?
4
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1answer
83 views

What triggers DNA to produce proteins?

What is the trigger for DNA to produce proteins or RNA? I have found enough material to study the inner workings of the cell and DNA; but, I can't find an explanation of the mechanics the cell uses ...
3
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1answer
45 views

Self pairing in DNA

I know that ssRNA molecule can fold over itself (e.g. in t-RNA). Can DNA do the same? Is there any example of this in nature? Why is this phenomenon more common in RNA than in DNA?
5
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2answers
184 views

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 ...