Can our own DNA be 'damaged'

[rich83]

As above.

Thanks

[Flibble]

DNA is damaged all the time, mostly it is repaired (or the damaged cell is destroyed), when that doesn't work you get cancer.

[Simpo Two]

Wot they said.

[rich83]

Thanks... that answers my question i think. :-)

Rich

[Simpo Two]

How much did you win?

[rich83]

anonymous said:

[redacted]

hahah :-)

[thatdude]

It can be, quite easily. If you wanted to induce mutations, a methylating agent (dimethyl sulfate, methyl triflate) is a usual sure-fire way to getting at DNA. I'm quite cautious about handling such reagents.

Curious...why did you want to know?

[hidetheelephants]

Paradox alert; one of the most damaging substances is oxygen, without which we wouldn't exist.

[thatdude]

hidetheelephants said:

Paradox alert; one of the most damaging substances is oxygen, without which we wouldn't exist.

Further info; It's a diradical!

[8Ace]

thatdude said:

It can be, quite easily. If you wanted to induce mutations, a methylating agent (dimethyl sulfate, methyl triflate) is a usual sure-fire way to getting at DNA. I'm quite cautious about handling such reagents.

Curious...why did you want to know?

When I did lab work I wasn't worried about toxic stuff, but was nervous as hell using MeI

[Simpo Two]

hidetheelephants said:

Paradox alert; one of the most damaging substances is oxygen, without which we wouldn't exist.

As O (free radical), yes, but not as O2 (molecule). We can do the table salt example too.

Going back to DNA, nicotine is a classic mutagen.

[evenflow]

^What he said.

Nicotine is not a mutagen.

It is highly poisonous though!

[Flibble]

Simpo Two said:

As O (free radical), yes, but not as O2 (molecule). We can do the table salt example too.

Going back to DNA, nicotine is a classic mutagen.

O2 is plenty damaging, when in radical form: http://en.wikipedia.org/wiki/Superoxide

[GeorgeK]

Simpo Two said:

hidetheelephants said:

Paradox alert; one of the most damaging substances is oxygen, without which we wouldn't exist.

As O (free radical), yes, but not as O2 (molecule). We can do the table salt example too.

Going back to DNA, nicotine is a classic mutagen.

The problem is that not all the oxygen used by the body is completely reduced to water. Various oxygen radicals and reactive oxygen species are formed in the process.
Nicoten is not a direct mutagen but some cellular studies have found it can induce DNA damage.

[Simpo Two]

GeorgeK said:

Nicoten is not a direct mutagen but some cellular studies have found it can induce DNA damage.

We used it (nicotine) as a mutagen in microbial genetics - but I agree that's not the same as someone smoking.

[BevR]

rich83 said:

As above.

Thanks

Yup, its happening on a surprisingly large scale all the time in every cell in your body. However your cells have a vast array of specialized components that either repair the damage or remove it and replace it with undamaged DNA.
When these fail you can end up accumulating mutations, this can be described as genomic instability and is regarded as an enabling factor in cancer. This is one reason why certain foods can be considered more dangerous than others with regard to cancer.

There are also a number of other clinical phenotypes associated with loss of some repair elements such as neurodegeneration, developmental issues and bone marrow failure.

If you want any more detailed information just give me shout.

EDIT: some numbers if anyone is curious (DSB= Double Strand Break, where the DNA is broken in two). This table is from a very good overview of the subject but is probably a lot more than you wanted and assumes at least a graduate level understanding of molecular biology. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC298887...

Edited by BevR on Tuesday 3rd February 16:27

[Blackpuddin]

What I want to know is, what advantage does this 'three-parent baby' thing bring? Surely only one egg and one sperm will be involved, as ever?

[BevR]

Blackpuddin said:

What I want to know is, what advantage does this 'three-parent baby' thing bring? Surely only one egg and one sperm will be involved, as ever?

Probably the quickest explanation is this video (excuse the cuteness):

http://www.thelilyfoundation.org.uk/animation/


The fertilized nucleus is transplanted into a donor cell that contains the mitochondria from a healthy volunteer. Mitochondria are passed down the maternal line so this gets round the problem, these mitochondria also have their own DNA and replicate independently of what you would normally consider 'your' DNA.

Its actually quite profound as it means that from that point on if the child is female her lineage will always trace 3 people instead of 2 as she will pass on the volunteers mitochondrial DNA.

There will probably be people who know more than me so I am happy to be corrected.

[Simpo Two]

That's about it.

What surprises me is how easily/quickly it was passed - without hordes of hairy-arsed hippy idiots waving banners and burning down scientist's houses.

I believe some bloke from the church was wheeled out and wheeled back in again.