Study: Lab test may identify dangerous gene mutations

Scientists say they have found a new way to help determine whether specific genetic abnormalities are likely to make people sick, a step toward avoiding a vexing uncertainty that can surround DNA test results.

Researchers used genetic engineering to create thousands of tiny variations in a gene linked to breast cancer, and tested each one in a lab to predict whether it would promote the disease if it appeared in a person.

When those predictions were checked against what scientists already knew about the BRCA1 gene, “we were very accurate,” said Lea Starita of the Brotman Baty Institute for Precision Medicine in Seattle.

The technique, which she and her colleagues hope to extend to other genes, is aimed at easing a frustrating problem in genetic testing. Sometimes those tests reveal an abnormality in a gene linked to the disease, but nobody knows whether that particular quirk is hazardous. It’s called a “variant of uncertain significance.”

Such a result can cause anxiety and worse: Experts talk about women who’ve had breasts removed after learning they had a VUS in a gene linked to breast cancer, only to find out years later that further research showed their variants were harmless.