MIT biophysicists have demonstrated that some cases of incomplete penetrance* are controlled by random fluctuations in gene expression, which could influence the mutations that can cause cancer.

Knowing the specific points in cellular pathways that are most important in controlling a cell’s response to mutation could give drug designers better targets for new therapies.

* Not every person who carries a mutated gene expresses the trait or condition associated with the mutation. Some of this variation may be due to environmental factors and the influence of other genes, but not all: It has been shown that genetically identical organisms living in the same environment can show variability in some incompletely penetrant traits.