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[From CRON4healthyfuture 2003-06-29]

Why the mitochondrial common deletion accumulates with age in certain tissues but doesn't actually do anything; Sao Paulo to the rescue.

Look, the common deletion may indeed accumulate in some tissues with age to
a *very* limited extent. But pinning it to any significant "pathology" of
aging has simply not occurred in recent experimentation.

These individuals have a hypothesis that might just explain the
descrepancy, and moreover it is biologically plausible.

Evolution "knows" about the common deletion, and has just used it like it
does everything else to design the organism that it wants. And so the
common deletion is just a "harmless" safety valve on your cells that

Med Hypotheses. 2003 Jul;61(1):60-3. Related Articles, Links

The common mitochondrial DNA deletion DeltamtDNA(4977): sheding new light
to the concept of a tumor suppressor mutation.

Dani SU, Dani MA, Simpson AJ.

Gene Therapy Center (CTG-AADM), Sao Paulo, Ribeirao Preto, Brazil

We propose that the age-related accumulation of DeltamtDNA(4977) mutations
may serve a protective function against tumor-promoting effects of other
somatic mutations. The evidence discussed here is consistent with the
concept that DeltamtDNA(4977) plays a tumor-suppressor role, thus sheding
new light to the concept of a tumor suppressor mutation. This concept may
help understand how a tumor-promoting mutation may be able to cause
malignant transformation in cells lacking a tumor-suppressor mutation,
while the same tumor-promoting mutation can be present in cells that carry
a tumor-suppressor mutation, without causing cancer.

PMID: 12781642 [PubMed - in process]