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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X-recessive disorder pedigree confusing me

This is a pedigree of a family in which bleeder disease, an x-recessive disease, is present. I am asked which marker, A or B, the disease is linked to. I've asked about this type of problem before: X-...
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69 views

Dynamic mutation and huntington's

I read that Huntington's is a disorder caused by dynamic mutations in the DNA, which means that a triplet sequence of DNA changes from generation to generation. Say we have the sequence ATGATGATGATG. ...
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54 views

Where to find gene manipulation video (or photos)

I hope Im not asking a dumb question! Where can i find video of gene manipulation in action under microscope? Like extracting a gene from a cell, fixing gene mutations, putting the gene in a vector, ...
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What is a genetic marker?

In DNA sequencing and analysis, what is a genetic marker? I've heard that microsatellites are genetic markers? Those are repetitive strands of bases such as GCAGCAGCAGCA etc. Why are they markers and ...
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2answers
99 views

Chromosomal translocation notation

A reciprocal translocation is denoted for example: t(4;12)(q32;q24) indicating that q32 on chromosome 4 being swapped with q24 on chromosome 12 if I understand this correctly. My question is: How do ...
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45 views

X-recessive disorders and genetic markers

Please observe the following pedigree of a family with a x-recessive disease (bleeder disease). The A's are genetic markers so close to the disease gene that recombination is negligible. I ...
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107 views

Pedigree problem and type of inheritance [closed]

Please observe the following pedigree and come up with a conclusion as to which type of inheritance is most likely Now it should be obvious that it's either autosomal dominant or autosomal ...
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1answer
47 views

Gene frequency problem

1/330 of white people in south Africa have a disease called Porphyri. What is the frequency of the gene if it is inherited autosomal recessive? This one I understand. The genotype frequency is $q^2 =...
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85 views

Walk me through microsatellite markers and PCR

Three polymorph microsatellite markers are used to try and narrow down the location of a disease locus, with the use of PCR with 2 flanks on each side of the actual polymorphic area. The PCR product ...
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107 views

Bayes theorem for mutations

MEN 2A is a dominant inherited disease caused by a mutation in the RET proto-oncogene. The probability of being sick when you have the mutation of the RET proto-oncogene varies with age and is assumed ...
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1answer
122 views

From a computer science perspective, how is DNA compared for various purposes?

I am very interested in privacy preserving technolgies, such as Microsoft PINQ and would like to see if this is applicable to DNA comparison. Given that I don't have a background in biology, I ...
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157 views

DNA extraction methods for hair?

TLDR: Can anyone state a extraction and isolation method(s) for genomic DNA for hair that will be used for PCR, in detail is preferable since I am a novice. I tried googling for DNA extraction ...
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CRISPR-Cas Systems

In the context of the bacterial systems (not the gene editing tool), I was wondering what happens to the foreign DNA after the Cas proteins have created a new spacer. It is really not clear to me, ...
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410 views

Does crude oil or kerogen contain ancient DNA?

According to wikipedia by the formation of oil there are a lot of organic materials present including DNA. Is it possible that this DNA is conserved somehow for millions of years?
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103 views

Can these “Promega Wizard genomic DNA Purification kit” be used for samples not stated directly?

I am not sure if this is a duplicate of my previous question, it is somewhat related, so sorry if I misunderstood. The question is, can i use the above kit for samples like hair, fingernails, etc? ...
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5k views

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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53 views

Help reading gene markers

I'm sorry if "gene markers" is not the correct word. An edit could be appreciated but I don't study in an English speaking country unfortunately. Question overview: In a family, there is a genetic, ...
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59 views

Why aren't genetic triplets roughly evenly found in DNA?

Sorry, the page I linked to is huge and you'll need to do a text search for "CG" to find the part I'm talking about. I found a graph on this page (http://www.oftenpaper.net/sierpinski.htm) showing ...
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2answers
894 views

What is the difference between sequence, reads, and contigs of genetic material?

Can someone explain the differences between sequence, reads, and contigs of genetic material such as DNA, if possible with an example? I am new to bioinformatics, and I have not found any conclusive ...
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0answers
86 views

Can DNA test of my grandparent's brother reveal my heritage from that branch of the family?

I'm thinking about doing that DNA test on all my grandparents to know where their genes come from. They are getting very old and I don't want to let the opportunity pass to gather more knowledge about ...
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240 views

Double stranded nucleic acids are more 'durable' than single stranded nucleic acids?

I'm struggling with a question I've been asked. "Why is double stranded genetic material more 'durable' than single stranded one?" I know that double stranded genetic material is more stable due to ...
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3answers
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DIY storing family DNAs' samples for future uses (eg medical)

I have a question I could not get an understandable reply from Google and I am no expert in the matter, so my plead to you is if you could give me practical and relatively easy to follow advice. With ...
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1answer
107 views

Mitochondrial D-Loop

I know that the D-loop is a DNA complex in which the strands of double helix DNA molecule are separated for a stretch and held apart by a third strand of DNA. Usually, this third strand has a base ...
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What exactly are computers used for in DNA sequencing?

I've thoroughly read the Wikipedia article on DNA sequencing and can't get one thing. There's some hardcore chemistry involved in the process that somehow splits the DNA and then isolates its parts. ...
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Why doesn't mitochondrial DNA accumulate damage over successive generations?

From what I recall, mitochondrial DNA is very susceptible to damage from oxidative stress because it is a site where free radicals are generated and their DNA isn't packed into chromatin like nucleic ...
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1answer
181 views

Does the DNA of a tadpole change after it becomes a frog?

Does the DNA of a tadpole change after it becomes a frog? In other words what changes take place as a tadpole becomes a frog, and does this metamorphosis affect the DNA in any way? I would appreciate ...
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2answers
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How accurate does the alignment of molecules in DNA have to be?

We have learned that the same information is saved in the DNA in the same place. So when DNA splits and then connects again (during reproduction); how does it maintain the integrity of the information?...
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132 views

Help reading chromatogram

A genetic variation is found in this chromatogram: It says that the "reference sequence" is the top line and that I can use the general genetic code to find the reading frame. I can see that there ...
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2k views

Does DNA polymerase always go the same direction?

I read that mutations are more likely to occur on "the strand that DNA polymerase replicates discontinuously". Does DNA polymerase always go replicate the same strand discontinuously, and if so, how/...
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96 views

DNA length and annealing kinetics

I have a mixture plasmids and undesired short linear fragments that share the same sequences. During denaturation and annealing, I would like the plasmids to 'find each other' before annealing to the ...
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489 views

Are there differences in DNA between humans of today and humans from 2000 years ago?

Are there any significant differences in our genome compared to the genes of our ancestors from 1000-2000 years ago? And if there are significant differences, do they result in significant ...
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71 views

Simplest Biological Organism? [duplicate]

What is the simplest biological organism from which a DNA sample has been or could be obtained? Could the resulting DNA be processed and examined in such a way that the resulting information would ...
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42 views

Forensic genetics- why is mtDNA comparison sometimes better than nDNA comparison?

Why is (in forensic genetics) in some cases more appropriate comparison of nuclear DNA but in some other cases comparison of mitochondrial DNA? Is it because geneticists are sometimes unable to find ...
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73 views

“Enhancers” of enhancers?

I am looking for examples (if any) of genomic regions which regulates the activity of enhancers, either augmenting or reducing it. Essentially some kind of enhancers (or repressors) of enhancers to ...
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152 views

What's the proton concentration around a DNA helix?

Let's suppose the concentration of a 20-nt DNA strand is $10^{-4}$M and the solution does not contain any salt ions. In a solution with pH 7, $[H^+]=10^{-7}$M, on average each DNA has only 0.001 ...
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92 views

Is it possible to insert DNA without cutting the recognition site with CRISPR/Cas9?

We are looking for a way to insert DNA into a genome, but we would like to do it in a way that the recognition site stay intact to be able to add again DNA at the same location. Do you know if it is ...
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2k 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 ...
6
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1answer
75 views

Why differentiated cells can't “undifferentiate” (under normal conditions)?

In a process called differentiation, the cells of the developing organism undergo huge changes, which result in cells, functioning "completely" differently. Two cells are considered to be of different ...
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227 views

How do genetic chimeras with different blood types not die?

If a person is a chimera and has two different blood types in his veins, how does he not die? Shouldn't the immune system attack one of the blood types? In 1953 a human chimera was reported in the ...
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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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242 views

Mitotic crossover happens in G1?

I was reading this article in wikipedia and came across this : It has been suggested that recombination takes place during G1, when the DNA is in its 2-strand phase, and replicated during DNA ...
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79 views

Nucleosome wrapping direction

Does anyone know which direction the nucleosomes are wrapped? I wonder: Relative to the B-DNA double helix twist direction (right-hand) Relative to the neighbor nucleosomes. Do they alternate to ...
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Inter-codon mutations statistical analysis

I am looking for a statistical approach to inter-codon mutations. For example a 64*64 (64*63 actually) table, that contain the possibility of mutation from one codon to another codon (CCA to CAA or ...
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2answers
90 views

RNA polymerase question

In this question we are examining a bacterial RNA polymerase that elongates at 20 codons per second. Question 1: How long will this RNA polymerase take to transcribe the Lac Z gene at 3510 base pairs? ...
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231 views

Do changes in an organism's cell modify the genetic information it uses for reproduction?

What I'm actually interested about is whether a modification in one cell during the life of an asexually reproducing organism affects its genetic information? Which cell's genetic information is used ...
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1answer
51 views

Are both (partial) copies of DNA transcribed in S and G2 phases of cell cycle?

For a little less than half the cell cycle, a significant number of genes are represented twice (just before dividing). Does the cell differentiate between these DNA in any way or are transcription ...
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869 views

Do transcription factors bind to both strands of DNA?

Do transcription factors (or generally proteins) bind to only single strand of DNA or both strands? Since it can have non covalent bonds to both strands in theory. I would like to know the mechanism. ...
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49 views

Can someone link me to resources on the efficiency of sticky end ligation?

I really would like to know if sticky end ligation could potentially be performed with very high efficiency, and which factors influence that. However, I can't find any papers on the subject, even ...
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1answer
126 views

How would you affect bulk DNA gene therapy for a human?

Let's imagine that we understood DNA programming and our genome very well and realized that there were some significant flaws (we die, we need sleep, etc.) And let's imagine that we understand how to ...
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Do DNA repressors exist?

I know about enhancers and the mechanism that lead them to increase the gene expression of their targets but I was wondering if similarly DNA repressors exist. I know about protein repressors but I am ...