Re: recombination question

On Mon, 9 Oct 2006 13:50:36 -0400 (EDT), "Perplexed in Peoria"
<jimmenegay@xxxxxxxxxxxxx> wrote:
snip



You are doing fine except you said "mitosis of the gametes". No doubt
you meant to say "meiosis".

Thanks and yes I did. I still get the name of the two inverted <Grin>


snip

Along the same lines as your question, crossover is somewhat
understandable as a random process for the 22 Somatic Chromosomes.
But what mechanism controls the crossover in the vastly different X
and Y Chromosomes?

My understanding is that the X crosses over in women (who have two of
them) during the meiosis leading to the egg. X does not cross-over
in men. Y never crosses over.

I've found several little bits of info say that
only the "common" gene area's in the X&Y crossover

A portion of the smaller Y has some of the same genes as X, possibly
attributes that have no way to directly express themselves in females
features of male genitalia etc but still present in X.

In other places what I've read is that the X contains almost the
entire Y Chromo, plus all it's own stuff (Intuition gene, Sugar and
Spice gene etc <BFG>)


(Especially if as Dawkins says it's not even on a "gene boundary " or
even on a specific start or stop code!)

That's what has me confused, if true by what mechanism
does it select only these common sections?

Sounds like a more complex code pattern than currently recognized
This seems like an area that could use some Nobel Prize level
research, and a simple newbie explanation!)


Thanks very much for the feedback
DB

.

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