Mitochondrial Steve?
There appears now to be good evidence that paternal mitochondrial DNA can occasionally be inherited. (See here.)
That’s right: paternal mitochondria, from Dad’s little wrigglers.
Sperms do contain mitochondria, but until now the usual doctrine (dogma?) has been that the egg always keeps them out, or kills them off if they manage to get in. (Though some, including the late John Maynard Smith, thought there was evidence to the contrary.)
It now seems that ‘always’ should be ‘nearly always’, and an occasional paternal mitochondrion gets through the egg’s defences. This could have implications for evolutionary ‘family trees’ and divergence times. Estimates have hitherto been based on the assumption that all mitochondrial DNA comes down the maternal line.
How important this is presumably depends on how rare is the occurrence. If it’s only one in a million, it may just be a minor curiosity, with no serious implications for evolution.
Posted by David B at 04:04 AM
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