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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How many generations does it take for the average descendant not to be genetically related to the ancestor?
Parent 1 and 2 have children. Assume infinite, randomly-mating population size. How many generations until the median descendant by lineage of parent 1 has 0 base pairs inherited from parent 1?
I ...
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Inheritance of child behavior based on daily life experiences of the parent
Our brain is a large network of neurons connected with each other.Our daily experiences change how our neurons are connected.Some experiences create better connections between two neurons A and B and ...
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Calculating pitch of B-DNA
From this question (How pitch of a DNA Helix is 3.4 nm?), I've learnt that for counting the number of axial rise for 10 base pairs in 1 helical turn to measure the pitch of B-DNA, we have to include ...
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Is it possible to proccess human genome in a local computer?
I have some basic programming knowledge, and I would like to take a look at my genome and search for specific sequences related to mental illness and addiction.
The test costs only 1000$ in Spain and ...
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What do alleles look like visually on linear DNA strands?
I've seen many textbook images of alleles on homologous chromosomes with the gene loci identified but how could this be visualised on linear DNA sequences with the bases written out? Is it that you ...
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Overlapping annotated regions among repetitive families of human genome
I am studying the repetitive elements in the human genome and I have come to know that some genomic locations are not uniquely described by a single repeat family. What's behind this uncertainty? Does ...
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What is the approx. diameter of a completely "folded up" human DNA molecule, in inches?
The human DNA molecule would be about 6ft if stretched out to a straight line.
I'm curious what the diameter of the DNA molecule normally is when it is "all scrunched up" or "bundled&...
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ddT-tailed TA cloning, and the fate of a double nicked plasmid in E. coli
In an undergraduate lab class on TA cloning, it was explained that ddNTPs are used as the substrate for terminal transferase when making the T overhangs of the vector. I was told this was to ensure ...
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What's the significance of DNA replication (S phase) before Meiosis?
From what I'm able to understand, Meiosis should end up with haploid cells with chromosomes having single chromatids (I don't know why it's necessary, but alright)
I understand that meiosis has a ...
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Start codon and 5' codon
Here it says:
For amino acid-based systems, the start codon of the mature protein is
labeled codon 1. The codon 5' to this is numbered -1.
So, I assumed the START codon is either -1 or 0.
But, when ...
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How pitch of a DNA Helix is 3.4 nm?
How pitch of a DNA Helix is 3.4 nm?
In the image that I have attached, the numbers with prime represent the number of base pair and normal numbers represent the number of gap elements between two base ...
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Does blunt end have a hydrogen bond?
I am an undergraduate student of biology.
I saw a lecturer online, who said that sticky ends makes phosphodiester and hydrogen bonds cut. (also here).
But why blunt end just makes phospodiester bonds ...
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Are DRB3 DRB4 and DRB5 different genes or different version of the same gene
From what I understand, an individual can hold up to two HLA-DRB345 alleles (but can be less) that can each be HLA-DRB3, HLA-DRB4 or HLA-DRB5.
However, since HLA-DQB1 and HLA-DQB2 are entirely ...
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what are average, median, and minimal dna closeness of stranger peoples, compared to closeness of relatives?
i thought: a parent closeness to a person can be marked as 50%. seems that is 50% of all parts of dna of humans that have variability across all human population. i heard that chimpanzees are 98% ...
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Must RNA and DNA be the way it is?
We're carbon-based based life form with (mostly) iron-based oxygen transportation for apparently good reasons.
Is the same true for why life on Earth developed using nucleotides, amino acids, RNA and ...
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How to quantify and measure phenotypic variation?
It is easy to quantify and measure genotypic variation, because genes are digital, like the 1's and 0's of a computer. You just check how many places the gene "letters" A,C,G,and,T differ. ...
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What does 'bend angle' of DNA mean?
Literally, what does the 'bend angle' of DNA mean?
I did some googling but I couldn't understand it.
How is it defined?
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How are probes in capture sequencing synthesized?
In capture sequencing it is common practice to use a panel containing ~10,000 probes. How are these DNA molecules synthesized? I imagine that there is a way to do this in parallel, but I haven't been ...
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If sufficienly many people are born, then is it possible that two persons are genetically identical although they are not twins?
It is my tought experiment.
Since for human, the genome information is finite, if so many many people are born,
then there exist two people who have the same genome although they are not a twin.
Is it ...
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What makes protein binding to the DNA random?
We know that the genetic recombination process in known as a random process. On the other hand, it has also been discovered that certain proteins (such as PRDM9) determine what recombination hotspots ...
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How do we know that the DNA we share with other species (especially primates) isn't fully the result of transposable elements?
I recently read a couple studies that concluded the 25% of genetic similarity between cows and reptiles is actually primarily due to TEs (transposable elements) rather than common ancestry.
Here's the ...
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Telomerase and End Replication in Eukaryote
Here is a picture of using telomerase in solving end replication problem (Courtesy: Molecular Biology of the Cell, Alberts, Garland Science Pub.)
Now lets consider the $3'$ end here, we are extending ...
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Can I have LAMP on the bench / in the field?
I am interested in LAMP for detecting small amounts of DNA (loop-mediated isothermal amplification and yes, I know the initials don't match).
I am trying to figure out exactly how clean/(sterile?) ...
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How do proteins 'know' where to go?
I've just found once again this famous animation I've been curious about for many years:
https://youtu.be/WFCvkkDSfIU?t=213
Here's a screenshot from the animation:
The green blobs (proteins, I ...
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Population structure and SNP's in Linkage Disequilibrium
I am reading about population structure and how you could as an example use plink to analyze a set of SNPs for individuals in a vcf file to identify a given population structure.
I know that LD can be ...
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Is Chimpanzee mitochondrial DNA identical to human?
How similar is chimpanzee mitochondrial DNA to human?
Does it show the same single ancestor?
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Why is DNA not single stranded? [duplicate]
From what I have researched DNA is not single stranded, because if it was single stranded, nitrogenous bases (the 'information' of the DNA) would be exposed to the cellular environment (although, I ...
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What happened to dead cells which still keep DNA information?
I heard that the destination of dying cells is either one of them: Apoptosis and Necrosis. Further I heard that apoptosis causes destroy of cell components and necrosis is caused by autolyses.
But we ...
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TMPRSS2 Primer Design
I am trying to design a primer for TMPRSS2 PCR reaction. However, this gene is in reverse position like in the picture I'll show.
From the nucleotide sequence I got from NCBI, should I reverse the ...
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CRISPR/Cas9: How can inserted DNA be used as a donor for the homology-directed repair if Cas9 only creates blunt ends?
The CRISPR/Cas9 method allows new genes to be inserted. After Cas9 cuts the Target-DNA, it can use a homologous piece of DNA as a donor template for homology-directed repair. But HDR only occurs when ...
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Can the genetic sequences for CRISPR components be inserted into the host genome so that the cell perpetually produces CRISPR components?
Theoretically speaking, can you insert the gene sequences for cas9, sgRNA, and promoters into the host genome so that the cell perpetually produces CRISPR components?
In this scenario, I'm guessing ...
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How are cells different depending on the ethnic origin?
I recently came across an article about the fact that cell-lines provided by merchant entities to give cells to researchers, were tagged by ethnic origin. The article especially speaks about ethnic ...
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How many cuts are done during CRISPR-Cas9 in one cell?
In a CRISPR-Cas9 experiment, the protein cuts the site matching the cRNA part of the gRNA. My question is: How many cuts are possible if multiples sites matching the cRNA are found in the cell?
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Can stand-alone DNA (no nucleus, no membranes, organelles...etc.) create cells? [closed]
I have been searching for an answer to the following question as part of my research but can't find a direct/complete answer yet.
Can stand-alone DNA (no nucleus, no membranes, organelles...etc.) ...
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Would a size-specific, electrophoresis-based RNA quantification kit work for ssDNA as well?
I'm using a custom library of ssDNA oligos to test the performance of some qPCR assays with mismatched bases in various primer and probe regions, and I'm trying to come up with a good way to verify ...
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EDTA in DNA extraction
I thought the EDTA solution binds to metal ions and deactivates the (metal-dependent) nuclease present in the cytoplasm which protects DNA from degradation. But I wondered how that would be the case ...
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Is deleting two or three consecutive nucleotides and inserting exactly two or three back more common than two or three consecutive SNP?
I am looking at cancer mutations. I found that some of the mutations are e.g.
c.1251_1252delGGinsTT
c.151_152delGGinsTC
c.351_352delCAinsTT
I wonder if these are indeed two consecutive single ...
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What percentage of our DNA is never transcribable? What percent is never actually transcribed into RNA unless researchers force it to in a lab?
From what I gather, the vast majority (but not all) of the DNA in our genomes will transcribe and create an RNA, if only under certain conditions in a lab (forcibly unwound, among other steps).
How ...
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Are there limitations in using DNase I hypersensitive sites (DHSs) to identify candidate enhancers?
Candidate enhancer regions are often defined in studies by DHSs and/or certain chromatin marks. I was wondering if DHSs are exhaustive for identifying possible enhancer regions, and if there is any ...
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Does Hydrogen bond strength relate to error rate?
The A-T connection has 2 Hydrogen bonds, whereas the C-G connection has 3.
Thus, the C-G connection is "stronger".
Looking at the RNA-polymerase, during transcription.
When trying to ...
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Is DNA with aprotic phosphate groups actually still a "nucleic acid"?
When looking at images for the structure of DNA I’ve noticed two versions for the phosphate backbone: one with protic phosphate groups (they have hydrogens making them resemble phosphoric acid) and ...
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drug-dna concentration
I want to understand how you calculate the final concentration of a Drug-DNA complex. I tried to mix equal concentration and volume of drug and DNA to form a complex and tried to see the absorbance ...
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Why are hydrogen bondings in DNA-RNA hybrids weaker than hydrogen bonds between two strands of DNA or two strands of RNA?
One of our professors asked this question and mentioned that "studies proved this". I can't find any answer.if someone knows a book, article,etc that can help or can explain the reason for ...
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Is TTGATATAT a gene?
Biologists use the sequence of letters A, C, T and G to model genomes. A gene is a substring of a genome that begins after the three-character ATG and ends before the three-character TAG, TAA, and TGA....
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Are DNA molecules negatively charged at low pH values?
We know, that for each monomer of DNA, phosphate groups are having -1 charge because one of the oxygen is negatively charged (2nd oxygen participates in the phosphodiester covalent bond), but isn't it ...
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DNA as a data storage medium: how many GB can a human genome store?
DNA molecules may be the digital storage medium of the future. I was looking at how much data you could fit if you would synthesize a DNA molecule the size of a human genome.
So DNA base molecules are ...
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Does an ORF need a stop codon?
I try to read ORFs from a gene sequence but I am not sure how to interpret a sequence with a start codon but no stop codon. Imagining I have a gene sequence like the following:
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Can gene mutations cause Down's syndrome in humans?
I am working on an A levels questions:
Which of the following statements about gene mutation is incorrect?
A. It can occur in both somatic and sex cells
B. It can cause Down's syndrome in humans
C. ...
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Are gene conversions and expansion/contraction of repetitive (satellite) DNA examples of directional, non-random mutations?
Are gene conversions and expansion/contraction of repetitive (satellite) DNA examples of directional, non-random mutations? For some context, it was brought to mind as a result of reading the ...
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Explanation for the results of Topoisomerase I treatment of ERCs - Gel Electrophoresis
This part of a 1997 paper published in The Cell (David A. Sinclair & Leonard Guarente, 1997) discusses the presence of extrachromosomal rDNA circles (ERCs) in greater numbers in old mutant yeast ...
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