Today's Globe: Partners probe, stem cell study for spinal injuries, smoking deaths, Galileo's eyes

Attorney General Martha Coakley has launched an investigation into whether the state's largest health insurance company and its largest healthcare provider may have illegally colluded to increase the price of health insurance statewide over the last nine years, according to several legal and government sources. The attorney general sent formal demands for information to Blue Cross and Blue Shield of Massachusetts and Partners HealthCare late last week, the sources say, calling for a detailed account of their contract negotiations in recent years.

Biotech company Geron Corp. says it plans to start the world's first study of a treatment based on human embryonic stem cells, a long-awaited project aimed at spinal cord injury.

Kentucky and West Virginia - where people traditionally smoke the most - have the highest death rates from smoking, a new federal study has found.

Italian and British scientists want to exhume the body of 16th-century astronomer Galileo for DNA tests to determine if his severe vision problems may have affected some of his findings.