Re-Write The Textbooks: Key Genetic Phenomenon Shown To Be Different Than Believed
Wednesday, July 1, 2009 - 23:14
in Biology & Nature
Because females carry two copies of the X chromosome to males’ one X and one Y, they harbor a potentially toxic double dose of the over 1000 genes that reside on the X chromosome. To compensate for this imbalance, mammals such as mice and humans shut down one entire X-chromosome through a phenomenon known as X-inactivation. For almost two decades, researchers have believed that one particular gene, called Xist, provides the molecular trigger of X-inactivation. A new study disputes current scientific belief by showing that X-inactivation can occur even in the absence of a gene previously thought to be the trigger of the process.