GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2006-05 > 1147737500
From: "brian quinn" <>
Subject: RE: [DNA] Methylation
Date: Tue, 16 May 2006 09:58:20 +1000
There's also epigenesis (the knitting pattern is how I look at it) which
accounts really for why we are so different from chimps- there is no way we
should be all that different just on the 25000 genes.
We are only about 4% different from the chimp that's about 24,000 genes
exactly the same and 1000 a bit different. It is how they are knitted
together to make the bits and pieces that determines the very important
differences- though that may only be in the level of abstraction we can
achieve by using language and analogy etc.
course for a mouse that's about 15,000 the same and 10,000 a bit different.
Bit worrying how similar we are to plants too. Our mitochondria is something
like the chloroplast in a plant. Shouldn't be too hard to add chlorophyll to
our skins and save doing some shopping, need to doctor the nuclear genome a
bit though :)
From: John Lerch [mailto:]
Sent: Tuesday, 16 May 2006 4:22 AM
Subject: [DNA] Methylation
One of the other contributors said that since we only have 25000 active
genes, there are a large number of ancestors who have contributed
nothing to us after 17 generations. (The correct number is 15 since log
base 2 of 25000 is a little less than 15.) WHAt about methylation? The
degree of turning on a region of our genes is determined by the degree
to which methylation can hide a region and that's determined by what
bases reside there. Doesn't that mean that all 3 billion positions on
the genome contribute in one way or another by varying the degree of hiding?
Even if it is 3 billion positions, that merely means that log base 2 of
3 billion = 34 generations have ancestors who don't contribute.
On the flip side. Is it really 25000? Aren't a large number of those
alleleles univalent--having only a single expression over the entire
human race? How many polyvalent alleles are they up to at present?
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