Doomed, We Are All Doomed!

us men that is,

it is all happening like this, the Y chromosome has been the symbol of masculinity, above Chromosome Y in red, next to the much larger X chromosome, the above graphic from the National Human Genome Research Institute, the thing is despite it being the carrier of the “master switch” gene, SRY, which determines whether the embryo will develop as “male” or “female”, the Y chromosome only contains very few other genes and is the only chromosome not needed in life. After all, women can live without one, through time, the Y chromosome has degenerated rapidly. While women have two perfectly formed X chromosomes, men have a shrivelled Y, if the same rate of degeneration continues, the Y chromosome has just 4.6m years left before it disappears completely. This may sound like a long time, but it isn't when you consider that life has existed on Earth for 3.5 billion years, the Y chromosome hasn't always been like this. If we rewind the clock to 166m years ago, to the very first mammals, the story was completely different. The early “proto-Y" chromosome was originally the same size as the X chromosome and contained all the same genes. However, Y chromosomes have a fundamental flaw. Unlike all other chromosomes, which we have two copies of in each of our cells, Y chromosomes are only ever present as a single copy, passed from fathers to their sons, this means that genes on the Y chromosome cannot undergo genetic recombination, the “shuffling" of genes that occurs in each generation which helps to eliminate damaging gene mutations. Deprived of the benefits of recombination, Y chromosomal genes degenerate over time and are eventually lost from the genome, will the Y chromosome disappear? The scientific community is still divided on this matter. But if the Y chromosome really does vanish, what will happen? Will all of us blokes disappear? no more Friday nights down the pub? this is all too much I will change the subject in the next post! for the full article have a look here, the next few million or so years does not look good for us chaps.