This mit Is Much More Interesting Than This Mitt

This is the boring Mitt, Mitt Romney the U.S. Republican presidential candidate:

As a Mormon, he believes a con man was a prophet of God who lives near the planet Kolob.  It's unclear what he thinks about the global challenge of climate change (what day is it?):

I find reality much more interesting than the nonsense he embraces.

Not too long ago, I had a post which described how some health physics deniers point to oxidative damage and use that to discount radiation damage.  It's bad math...they're trying to claim that oxidative damage happens a bunch (let's pick a unit-less number of 100,000) and radiation damage is smaller (lets say 1).  Therefore, so the fantasy goes, 100,000 +1 =0...no risk from either.  But for those of us who accept math we know the answer should be 100,001, a combined risk.

The much more interesting (and reality-based) mit, is that of mitDNA, where mit stands for the mitochondria, the cell's power plant.  It's not just your nucleus which has DNA (inherited from Mom & Dad), your cells' mitochondria have DNA (inherited only from Mom):

You may know that your nuclear genome has around 25,000 genes, but your mitDNA only has around 37 genes.  This is strongly suggestive of endosymbiosis...that our cells are the result of symbiotic relationships formed long ago between separate cell types.

That alone is awe inspiring and is a huge obstacle for another group of science deniers called IDiots (Intelligent Design proponents).  Why would an Intelligent Designer package two sets of DNA, one in very hazardous environmental conditions (the mit)?

Oxidative damage occurs primarily in the mitochondria because that is where cell metabolism takes place.  Radiation damage can occur pretty much anywhere, and it's been its effect on nuclear DNA that's been mostly studied.

But what about radiation damage to mitDNA and its role in cancer?

We don't know much about that.  mitDNA has fewer repair mechanisms and higher copy number than nuclear DNA.  Copy number means there are mitDNA segments which are duplicated, so that damage can be coped with using redundant mitDNA segments instead of repair mechanisms.  The copy number seems to increase after irradiation.

The mitDNA also isn't packed as tightly as nuclear DNA and we know that mitochondrial dysfunction is observed in cancer cells.

So just what is going on is unclear, but-