GENEALOGY-DNA-L Archives

From: "Bonner, Gregg" <>
Subject: [DNA] mtDNA inheritance from father
Date: Mon, 26 Feb 2001 17:28:26 -0500

I think it may be useful to examine the roles of the sperm and the egg in
the very early parts of the fertilization process. The egg is there to give
its 1/2 of the DNA AND to provide some nutritive matrix. The sperm is there
to provide its DNA, and that is pretty much it. The sperm must make its way
to the egg, however, and needs energy to get there. Therefore it will need
mitochondria. Hence sperm have mtDNA.

The misperception is that the whole sperm enters the egg. It does not. Most
of the sperm is there only to get the sperm to the egg, and nothing more.
Hence the tail and most of the rest of the sperm are shed, and the sperm DNA
is sort of 'injected' into the egg.

Also note that the egg is a LOT bigger than the sperm, and the egg is also
loaded with mitchondria.

So the moral of the story is this: sometimes the sperm's mitchondria are not
shed perfectly, and the father's mtDNA could be propagated, however, the
mother's mtDNA would overwhelm it in number so that it would be hard to find
the father's mtDNA, even if it is present. I think it is a rare enough
situation to discount its importance in genealogical reconstruction.
Nevertheless, if I were to do a mtDNA study for myself, I would want to find
members of an all female lineage which come from a daughter that is NOT my
ancestor as far back as I could, to control for this possibility as much as
possible.

Cheers,

Gregg

This thread:

• [DNA] mtDNA inheritance from father by "Bonner, Gregg" <>