Identical Cells Can Exhibit Random Differences

At any given time, individual cells, even those in a genetically identical group, are at various stages of their life-cycles. The variation in gene activity during a cell's life-cycle results in a genetic cacophony scientists call "noise." Multicelled organisms can have trillions of cells, and at full crescendo, their noise may contribute to physical differences even in identical twins or cloned animals.

Now, researchers at the University of California, San Diego, are using advanced molecular biology techniques coupled with sophisticated mathematical models to tease apart the components that make up this noise, which appears to be involved in development, evolution and even some genetic conditions.