President Bush yesterday signed legislation into law that will bar health insurance companies or employers from denying or canceling coverage, hiking premiums or making decisions on hiring, firing and compensation based on genetic test results.

The Genetic Information Nondiscrimination Act of 2008 (GINA) sailed through the Senate in late April, following a year of political wrangling, and a week later passed the House by a 414-to-1 margin.

Rep. Louise Slaughter (D-N.Y.), a microbiologist with a master's degree in public health, introduced the first genetic antidiscrimination legislation 13 years ago. GINA supporters believe the act will encourage people to take advantage of the more than 1,000 genetic tests now available to diagnose and assess risk of diseases without fear of losing their jobs or being denied insurance coverage for doing so.