4 ms·
I thought in females half of X chromosomes are deactivated as to not producing conflicting similar proteins. If the extra cone gene is on the deactivated half,
by peter303 11y ago
I thought in females half of X chromosomes are deactivated as to not producing conflicting similar proteins. If the extra cone gene is on the deactivated half, then it is not produced.
It is suggested that imperfect deactivation leads to female increased occurrence of autoimmune syndromes over males.
- akavi 11y agoThe key is that which X chromosome is deactivated is not the same in all cells. It does occurs fairly early in the development process (a stage called gastrulation), and the deactivation does persist for all cells that descend from a given cell present. But critically, it's late enough that a retina could conceivably possess cells descending from two different "lineages". You can actually visibly see the "resolution" of the deactivation by looking at tortoiseshell cats. Each blotch of orange/black represents one cell present at the deactivation stage.