9
votes
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Why AZT is selective towards HIV and doesn't impair human DNA replication?
Retroviruses depend on being able to convert their RNA genome into a DNA copy, and have a reverse transcriptase enzyme to do that. This unique activity is not found in human cells, allowing for ...
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8
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If everybody DNA is different then how blood can match even with matching blood group?
A few components to my answer.
Red blood cells do not contain a nucleus, therefore, they do not harbour DNA.
The major determinant of blood compatibility is the blood antigen. There are only 4 types: ...
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6
votes
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How does non-homologous end joining (NHEJ) work?
Non-homologous end joining indeed induces errors in the affected sequence. But you have to keep in mind, that NHEJ is an emergency repair mechanism which involves a "repair or die" chance. If the ...
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6
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Repair wrong DNA pair after ending replication?
DNA mismatches and indels can be repaired after replication through an aptly named mechanism called DNA mismatch repair.
I'll briefly describe the mechanism in Escherichia coli, but it's similar in ...
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6
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How does NHEJ cause indels?
This is a very interesting question and I had not thought about it before. I am reiterating the background of your question.
Background
Cas9 cuts the both the strands of the target DNA at the same ...
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6
votes
Does the second law of thermodynamics cause aging?
Second law of thermodynamic and ageing
The second law of thermodynamic applies to closed system. Organisms are not closed system. The second law of thermodynamic is a fundamental principle of our ...
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6
votes
Why does ionizing radiation cause only DNA double strand breaks?
Ionizing radiation does cause single-strand breaks and other kinds of DNA lesions that are not double-strand breaks. However, double-strand breaks are the most difficult to repair and are thus the ...
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5
votes
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How to safely conserve my current DNA methylation marks?
To record the current methylation state of your DNA, you can use bisulfite sequencing. Basically, you take half of your DNA sample and treat with bisulfite, which deaminates cytosines (C->U) , so they ...
- 3,254
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How does DNA damage cause ageing in yeast?
In eukaryotic cells there is no difference between a mother and a daughter cell - the later is an exact copy of the mother cell. This is true for yeasts as well for example for human cells. The only ...
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5
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Is each generation getting older?
In germ cells telomerase enzyme is active and elongates telomeres, so youngsters are not born older than their parents due to telomeres.
Still, they do receive mutations, accumulated by their parents'...
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5
votes
Is there a point in our life when ALL the atoms from our childhood's body get replaced?
Is there a point in our life when ALL the atoms from our childhood's body gets replaced?
No. There is no point where ALL atoms have been replaced.
This has been shown by tracing distinct carbon ...
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4
votes
The damage of cancer cells
Cancer is commonly defined as uninhibited cellular replication caused by mutations to the genome.
Genes where cancer-causing mutations have been identified are known as oncogenes; the COSMIC (...
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4
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How does DNA damage cause ageing in yeast?
Background to the different theories of ageing.
This video, from a senior lecturer at the University of Liverpool who specialises in ageing, discusses the theories of ageing. He touches on the DNA ...
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4
votes
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Are missing limbs hereditary?
Does this mean that if one (or both) parents have something major missing (like a limb), the kid will come out without a limb?
Unless there is a genetic basis to the missing limb, no. Even for people ...
- 2,227
4
votes
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meaning of "usually greater than 200 base pairs"
No, similarity is not measured in base pairs. They are talking of regions of cross-over being marked by at least 200bp of highly similar sequence between the two strands involved in exchange.
- 1,294
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What do white blood cells do with FOREIGN white blood cells?
Okay, you have a lot of questions there. I'll try to give some answers, but if you want more details or background knowledge I'd recommend you to read /study more about immunology (none of your ...
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4
votes
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Replacing, instead of repairing, DNA
It seems very feasible to synthesize human DNA (please inform my
ignorance, if I'm wrong. lol.) and it looks very promising after
reading this:
https://www.wired.com/story/live-forever-synthetic-...
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3
votes
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Are nucleotides at the ends of DNA stripped on aging?
The Stanford article that you read is correct, in the sense that telomeres do not need to be completely removed by cell division before deleterious effects occur and cells start undergoing senescence. ...
- 9,304
3
votes
How does non-homologous end joining (NHEJ) work?
NHEJ is indeed error prone. It is called "non-homologous" because it does not use a "homologous" template from another sequence-matching piece of DNA to guide the repair. Homologous repairs avoid ...
3
votes
If everybody DNA is different then how blood can match even with matching blood group?
Because one's DNA doesn't have to exactly match another person at all 3 billion locations for the transfusion to be successful. As it turns out, there are only a few proteins that determine whether a ...
- 4,680
3
votes
Which frequency of UV light damages DNA?
Not only pure DNA, UV radiations are one of the main causes of skin cancer because they damage cellular DNA in skin cells. Talking about frequency range, two different types of UV radiations damage ...
3
votes
Does it make sense to make my own DNA copy (kind of backup) while I am young?
While your DNA gets damaged, not every single cell will have the same damage. Your consensus DNA sequence will not change.
- 4,680
3
votes
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How can DNA replication result in hair pin structures?
DNA Hairpins are formed when two regions in same single stranded DNA are complementary in nucleotide sequence but in the opposite directions (as represented in image below). These two sets of ...
- 1,287
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votes
If everybody DNA is different then how blood can match even with matching blood group?
It is critical for you to realize that one's DNA is not the determining factor when it comes to a blood transfusion. Rather, what you have to look at is the proteins being expressed by the DNA coding ...
- 51
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How do nicks in the DNA strand affect the success of Long Range PCR?
It is not unlikely that nicking is causing trouble. The question is if repeated freezing and thawing is causing the problem, there is an article which has been published in B.R.L. Focus in 1983 which ...
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2
votes
RF Cautery DNA damage?
The EMF/RF doesn’t directly damage the cell. It just deranges cellular metabolism.
The free radicals that are produced by this change in metabolism are what causes the damage.
OXIDATIVE STRESS AND ...
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votes
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RF Cautery DNA damage?
The thing about DNA is that it's very durable, compared to the rest of the cell. It's not too difficult to extract DNA from cooked and processed food, even though the definition of "cooked" is "...
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How can we create a living dinosaur using DNA technology?
It is widely accepted that birds are in fact dinosaurs. Cladistically speaking, no DNA technology is required to create a living dinosaur, as they already exist.
Assuming you want to do the same to ...
- 9,304
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Questions on DNA damage
Excellent question!
You would definitely be able to find quite a few sequences of DNA that are undamaged (in fact most of them would be undamaged), but it is very unlikely that any cells in his/her ...
- 1,846
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How do mutations actually occur?
Mutation of DNA can be caused by an exogenous or endogenous source. Many external factors like irradiation or chemicals induce mutations. Some endogenous mutations arise from oxidative stress, ...
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