GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2010-02 > 1266220162


From: "Lancaster-Boon" <>
Subject: [DNA] "counting mutations" versus "GD from the modal"
Date: Mon, 15 Feb 2010 08:49:22 +0100


Dear Anatole:

You write (to Sasson) that "terminology is always developing" and in many
postings you have blamed pretty much everyone for being fuzzy in THEIR
language. Presumably we should understand that you are claiming that the
metaphor of counting mutations deserves precedence over "genetic distance"
because it more clear than the way other people write?

To Sasson you wrote:
Every single change of an allele, which makes it shorter or longer, it is a
mutation.

However, this is very simply not correct. These are normal English words
also, so you can not define them in a new way unless you are really trying
to make communication difficult. You simply are not counting mutations. You
are counting deviations from a modal and using these as an estimate of
mutations from an ancestral haplotype.

What's more, in other posts, for example to John Marsh, you made is clear
that thinking too much about actually trying to count real mutation events
is the wrong approach. It is an important point TO YOU that people should
not mix up the estimation with thinking you are counting real events that
happened in the past and are no longer visible. Instead you say that we
first need to examine how (un)likely they are etc.

So in my opinion you should do more to take your own advice and use clear
language, not fuzzy language. If you find that your personal metaphors are
causing confusions then the best approach is surely to use the language that
works.

Actually it is often easy to think about what makes new scientific metaphors
work or not. Many of them fail because they imply something that has no
prarallel in the model being explained. If you use the term "first order"
(as you do) it implies there is a second order (which in your case you
blamed me for assuming from your words). And if you use the metaphor
"shallow" it implies the contrast is to another situation which is "deep"
but in your recent discussion, once again, I have been told quite sharply
that you have a methapor which does not work in the obvious way.

Best Regards
Andrew


This thread: