Thank you for the information you shared, Brian!? I knew the PAR regions of the X and Y chromosomes can undergo recombination but didn't realize the centromeres of a male's X and Y could also recombine.? That makes sense, then, that the instability referenced has to do with recombination
Mary
On Wednesday, March 27, 2024 at 02:50:17 AM EDT, Brian Swann <brian_swann@...> wrote:
Hi Mary
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I think this makes sense.? We are talking about different domains of the Y-Chromosome.
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The PAR regions are at the ends of the X- and Y-Chromosomes, whereas as its name suggests the centromere is at that pinch point between the long arms and the short arms of the
chromosomes. Recent work on cell biology has done a lot of work to examine in detail how the centromere and associated cell features such as histones and chromatin go to form the mitotic spindle, which is the cell apparatus which pulls the two sets of chromosomes
apart when copying has been completed.
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During this copying process the genes from the father and mother get shuffled (recombination) ¨C except for certain regions of the Y-Chromosome.? That is what enables us to track
male lines with surnames. But that shuffling can happen in the PAR regions, and I think in areas around the centromere too.
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Somewhere, I have listed out the ¡°start¡± and ¡°stop¡± marker positions of the human reference Y-Chromosome sequence which relates to the various domains of the Y-Chromosome.? This
is all moderately simple until you start to ask cell biology type questions ¨C like ¡°What really determines marker mutation rates¡±, or ¡°How does the Y-Chromosome really get copied¡±. ?Or ¡°Is the Y Chromosome relevant to any medical problems outside of fertility-type
problems¡±; ¡°What is the function of that huge tail of heterochromatin on the Y-Chromosome, if anything¡±.
