On a long journey, one wrong turn early on can send you off in completely the wrong direction, whereas a misstep near the destination might be easily rectified. Similarly, when things go awry in early development, while the body is still putting itself together, the repercussions can be severe. Tuberous sclerosis complex is a disease that causes abnormal growths around the body, and can also cause mental disabilities and seizures. It is caused by a genetic mutation in the brain that occurs early in embryonic development. Now researchers have found that the timing of this mutation dictates the intensity of the symptoms. When the mutation occurred in the brain of an 18-day-old mouse embryo (pictured), the symptoms were much less severe than for those who experienced the mutation after 12 days. This discovery might lead the way to new treatments, and shows that timing really is everything.
Written by Anthony Lewis