The Act was passed last year and signed by then-President Bush.
It makes it illegal to base insurance eligibility or even rates on genetic data, including family histories. Some insurers had been giving discounts to people who completed family history questionnaires. No more.
Employers are already complaining. Some say common health risk assessments will no longer be legitimate. Some complain that wellness programs will be hurt.
Basically the new law puts your family history, including your genetic make-up, under requirements similar to those of HIPAA. Just as doctors can't share your medical data with outsiders, they can't share your family history either. This may require changes to Electronic Health Record (EHR) software, especially on the server side.
The New York Times says the law will have some unintended consequences. If a CEO's father and grandfather died of heart attacks at age 50, and the board refuses to promote him to the top chair at age 49, he could have a tort.
Some data can still be collected. There's a "water cooler" exception, so if you tell the boss about your mom's breast cancer they can hear that. Or if they later read her obituary in the paper. Or if they ask why you took family leave and you say it's because your dad has pancreatic cancer.
GINA may be impacting you right now, because many companies are engaged in "open enrollment programs" for next year's health insurance. There are no longer discounts for giving the insurer data. Some analysts think the new law is America's definitive statement that they don't want insurers playing their present expansive role in the health care system.
As with everything, there are unintended consequences. Some baseball teams have used genetic tests to identify (and set the age for) players from Latin America. One basketball team refused to re-sign a player without a genetic test. Perhaps, as Roberto Duran once said, no mas.
One more thing. The blog Queerty notes that if they ever find the the "gay gene" employers can't test for it, nor discriminate against you based on it. They'll have to rely on finding your two tickets to "Gypsy", or meeting your companion at the company picnic. (Hey, I love "Gypsy.")