DNA - Can you enlighten?

Dear Todd,

Like many, DNA is a very mysterious world to me. The discussion at the moment is very interesting. There is one aspect I wonder about, but more wonder whether I am wrong.

A person gets 50% of DNA from his/her father and 50% from his/her mother.

Now that 50% from the father, where did that come from? Does he pass on half of _his_ father and half of _his_ mother? So that the grandchild would have 25% from each grandparent?

I read somewhere that a person could have an ancestor, many generations ago, and not have any DNA from that ancestor, is that correct?

I think, I am not the only one wondering about this.
Look forward to hearing from you.
Leo van de Pas

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Relevant Pages

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