More women may benefit from gene testing for hereditary breast or ovarian cancer, especially if they’ve already survived cancer, an influential health group recommended.

At issue are BRCA1 and BRCA2 genes. When they’re mutated, the body can’t repair damaged DNA as well, greatly increasing the chances of breast, ovarian and certain other cancers. BRCA mutations account for 5 to 10% of breast cancers and 15% of ovarian cancers. But mutations cluster in families. The U.S. Preventive Services Task Force expanded its screening advice, telling doctors they should also assess women’s risk if they were treated for breast or other BRCA-related cancers, and now are considered cancer-free or their ancestry is prone to BRCA mutations, such as Ashkenazi Jewish women.

Dog owners may have healthier hearts

Owning a dog may be good for your cardiovascular health. That is the conclusion of a study of a randomly selected group of 1,769 Czech residents of Brno. Researchers scored them on the American Heart Association’s seven measures of heart health: blood pressure, cholesterol, blood sugar, physical activity, diet, body mass index and smoking.

Owners of any pet scored higher than those who didn’t own a pet, but dog owners scored higher than both. Dog owners were more likely to report sufficient physical activity, a better diet and good glucose levels than the rest of the group. “Owning a dog increases the sense of well-being in general, decreases loneliness and decreases rates of depression,” said the senior author, Dr. Francisco Lopez-Jimenez, a cardiologist at the Mayo Clinic. “All these factors also relate to cardiovascular health.”

Air pollution, even modest levels, deadly

An international team of researchers used data from 652 cities in 24 countries to correlate levels of particulate matter pollution with day-to-day mortality rates. They measured the concentrations of two microscopic particles of soot, PM 2.5 and PM 10, particles small enough to enter the lungs or the bloodstream.

The study, in the New England Journal of Medicine, found that as the concentration of particulate matter increased, so did the number of excess deaths. In the U.S., there was a daily mortality increase of 0.79% for each 10 micrograms per cubic meter increase in PM 10 and a 1.58% increase for each 10 microgram increase in PM 2.5. This would translate to an extra 178 deaths on a day when levels of these pollutants increased by these amounts.

The Environmental Protection Agency sets a three-year daily average limit of 12 micrograms of PM 2.5 and 15 micrograms of PM 10. “Lowering the present U.S. limits could reduce the number of deaths,” said a co-author, Antonio Gasparrini of the London School of Hygiene and Tropical Medicine.