Apparently, if you have the C150T mutation in your mitochondrial DNA, you stand a good chance of getting old. Very old.
Seventeen percent of a group of 52 Italians between 99 and 106 have it, while only 3.4% of 117 people under 99 had it. That's statistically significant, but we still don't understand how the mutation appears (is it inherited or is it a mutation that occurred after conception) or how this affects lifespan (does it contribute to accelerated replication?).
Here's the link to the PNAS 100 (3) 1116-1121 Feb 4 2003 abstract.
What I always found intriguing about mitochondria (wow, there's a cocktail conversation stopper...) is that they use a prokaryote coding scheme, and replicate completely independently of the surrounding (eukaryote) cell. What this probably means is that at some distant point in eukaryote ancestry we had a commensal relationship with a prokaryote, which slowly lost its independence and identity.
Flash to a future actuarial table:
Flash to a future breakfast cereal advert:
"...New! Loaded with mito-DNA enhancing minerals!"