According to O'Shea, randomness in gene express could have important evolutionary and biological implications, both advantageous for cells and deleterious. For example, mutations in genes could change their noisiness independent of the effect of the mutation itself. Noise in essential genes could be deleterious for a cell. However, noise could also produce diversity in populations of cells with the same genetic makeup, and this diversity could make them more adaptable to changes.

Another effect of randomness in gene expression might be observed, for example, in cells with two slightly different copies of the same gene, where one might be noisier than the other. Such noise might also produce variability among cells that might offer evolutionary advantages.

Noise in genes might also be a trigger for the formation of tumors, said O'Shea. In cases where cells lose one copy of a gene through mutation, the reduction in gene number increases the noise in gene expression. This increase in noise makes it more likely that the remaining gene might alter its activity to trigger uncontrolled proliferation.

Noise could be necessary for normal development of some biological systems, said O'Shea. For example, when olfactory neurons in the developing embryo are deciding which of a multitude of possible odorant receptors they will produce ” a choice that is final ” random noise in gene expression might be necessary to enable this decision, she said.

O'Shea said that her group plans to continue this line of research and hopes to identify in which cases such randomness is beneficial to an organism. Then, they will alter the level of noise and determine how it affects the fitness of the organism. They also want to follow noise production in a single cell over time ” rather than in populations of cells ” to explore in more detail how noise is produced.

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