Scientists have discovered that the Y chromosome uses a neat trick to repair its most crucial genes, a strategy that apparently helps keep it from rotting away over evolutionary time.
Instead of doubling up to protect its genetic cargo like other chromosomes, the lone Y safeguards its genes by having sex with itself, an international consortium has found. Proving perhaps that nature has a sense of humor, scientists have discovered that the Y chromosome - the one that makes a man a man - has a remarkable ability to make do-it-yourself repairs.
June 20, 2003 — The human male sex chromosome does have the ability to repair itself and may not be headed for extinction as had previously been thought, according to a surprising new study.
A 40-strong team of researchers led by David Page of the Whitehead Institute at the Massachusetts Institute of Technology, report their findings in this week's issue of the journal Nature.
As well as having a previously unknown and elaborate back-up system for self-repair, the Y chromosome also carries 78 genes.
"The Y chromosome is a hall of mirrors," said Page, whose team has for the first time identified the full genetic sequence of a Y chromosome, from an anonymous donor.
Both the male Y and female X chromosomes are thought to have originally been the same size, but after the Y took on the sex-determining role for maleness it apparently began to lose genes. At this time it also lost the ability to pair up exactly with its partner and to swap faulty genes for good ones, as the other 22 pairs of non-sex chromosomes do.
Earlier studies had suggested that the Y chromosome carried only a few dozen genes, compared with more than 1,000 known on the X chromosome.
A team of Australian researchers led by Jenny Graves, of the Research School of Biological Sciences at the Australian National University in Canberra, previously found that the Y chromosome had been losing five genes per million years. Graves had thus predicted that the chromosome might be heading for extinction within five to 10 million years.
But Page said that the Y's full genome sequence has revealed that scientists generally had underestimated both its number of genes and its powers of self-preservation.
The team believes the Y has developed an apparently unique way of pairing up with itself. They found that many of its 50 million DNA "letters" occur in sequences known as palindromes. Like their grammatical counterparts, these sequences of letters read the same forward as backward but are arranged in opposite directions — like a mirror image — on both strands of the DNA double helix. This means that a back-up copy of each of the genes they contain occurs at each end of the sequence.
When the DNA divides during reproduction, the team believes, it opens an opportunity for genes to be shuffled or swapped and faulty copies to be deleted.
Instead of doubling up to protect its genetic cargo like other chromosomes, the lone Y safeguards its genes by having sex with itself, an international consortium has found. Proving perhaps that nature has a sense of humor, scientists have discovered that the Y chromosome - the one that makes a man a man - has a remarkable ability to make do-it-yourself repairs.
June 20, 2003 — The human male sex chromosome does have the ability to repair itself and may not be headed for extinction as had previously been thought, according to a surprising new study.
A 40-strong team of researchers led by David Page of the Whitehead Institute at the Massachusetts Institute of Technology, report their findings in this week's issue of the journal Nature.
As well as having a previously unknown and elaborate back-up system for self-repair, the Y chromosome also carries 78 genes.
"The Y chromosome is a hall of mirrors," said Page, whose team has for the first time identified the full genetic sequence of a Y chromosome, from an anonymous donor.
Both the male Y and female X chromosomes are thought to have originally been the same size, but after the Y took on the sex-determining role for maleness it apparently began to lose genes. At this time it also lost the ability to pair up exactly with its partner and to swap faulty genes for good ones, as the other 22 pairs of non-sex chromosomes do.
Earlier studies had suggested that the Y chromosome carried only a few dozen genes, compared with more than 1,000 known on the X chromosome.
A team of Australian researchers led by Jenny Graves, of the Research School of Biological Sciences at the Australian National University in Canberra, previously found that the Y chromosome had been losing five genes per million years. Graves had thus predicted that the chromosome might be heading for extinction within five to 10 million years.
But Page said that the Y's full genome sequence has revealed that scientists generally had underestimated both its number of genes and its powers of self-preservation.
The team believes the Y has developed an apparently unique way of pairing up with itself. They found that many of its 50 million DNA "letters" occur in sequences known as palindromes. Like their grammatical counterparts, these sequences of letters read the same forward as backward but are arranged in opposite directions — like a mirror image — on both strands of the DNA double helix. This means that a back-up copy of each of the genes they contain occurs at each end of the sequence.
When the DNA divides during reproduction, the team believes, it opens an opportunity for genes to be shuffled or swapped and faulty copies to be deleted.
by John Ronane January 31, 2004
Chromosome which is found in both males and females. XY = male. XX = female. Sperm can be either an X or Y chromosome. During fertilization, if the Y chromosome sperm reaches the egg, then the baby is a boy. If the X chromosome sperm reaches the egg, then the baby is a girl.
Think of it as females having two copies of the same CD music album in every cell in their body, while males have one copy of that album in every cell in their body(x chromosome) and an extra single CD (the y chromosome) also in every cell in their body.
Even if the y chromosome was suffering from genetic degredation(which it is not) the effect could easily be reversed by genetic engineering.
Even if the y chromosome was suffering from genetic degredation(which it is not) the effect could easily be reversed by genetic engineering.
by John Ronane April 8, 2004
there was an alien dimension, our astrosmers met them on a planet called smerstation, they were wearing turbans but when we came into contact with the smeralienese people they said they were head beanies now dont mistake them as they had white chromozone layers
by smrsarenazis March 11, 2017
A Chromosome Gnome refers to a man or woman with small stature that either has down syndrome or shows similar mannerisms to someone on the autism spectrum.
by Gluey and Gooy June 24, 2019
by Thigh_Exercise January 16, 2017
The Shadow of the Elder God Ochwar. He can destroy entire realities with ease. He can suck Chromosomes out of any mortal, and it makes him even stronger.
by Succpreme March 5, 2019
PUT THE CHROMOSOMES IN THE BAG!!!!
by Loafus Crambwell May 6, 2019