Now it’s time to revise the high school biology textbooks as a new study says the shape of X-chromosomes is not X, as it is believed, but somewhat like ‘O’.
The new finding says X-shaped chromosomes are in fact much more complex and look much messier. That’s the finding of a new project that relied on DNA sequencing to produce accurate 3D images of chromosomes.
Scientists say, the first 3D models of chromosome structure have overturned a long-held belief about their shape – the X chromosome looks nothing like an X!
Scientists at the Babraham Institute in UK, working with the University of Cambridge and the Weizmann Institute, have produced beautiful 3D models that more accurately show their complex shape and the way DNA within them folds up.
“The image of a chromosome, an X-shaped blob of DNA, is familiar to many but this microscopic portrait of a chromosome actually shows a structure that occurs only transiently in cells – at a point when they are just about to divide,” Dr Peter Fraser of the Babraham Institute, said.
“The vast majority of cells in an organism have finished dividing and their chromosomes don’t look anything like the X-shape. Chromosomes in these cells exist in a very different form and so far it has been impossible to create accurate pictures of their structure,” said Fraser.
This latest research, published in journal Nature, puts DNA into its proper context in a cell, conveying the beauty and complexity of the mammalian genome in a far more effective way than volumes of text previously have.