PARIS : French doctors said on Friday they had used gene testing to help women with advanced breast cancer get access to clinical trials that may offer a better chance of treating their disease. The study improves the chances of getting drugs that, like a sniper’s rifle, aim at a specific type of tumour, they said. Researchers led by Fabrice Andre, a professor at the Gustave Roussy Institute in Paris, unravelled the DNA of cancer cells found in more than 407 women whose breast cancer had spread dangerously to other tissues.