Has DNA Testing Prevented Disease?

A technician handles a DNA sample at a Prenetics Inc. laboratory in Hong Kong, China, on Friday, Jan. 26, 2018. 

Photographer: Bloomberg/Bloomberg

Hi folks, it’s Kristen in New York. This week, a reader wonders whether genetic testing has had much impact on rates of disease. But first ...

I have a CHeK2 mutation that was discovered after my younger sister was diagnosed with early-stage breast cancer. I am now considering a mastectomy. My daughters also have this gene. So, I wonder if more testing for these less common mutations has led to better health for people? Kalista, Anacortes, Washington