Washington ? The first federal anti-discrimination law in nearly 20 years takes effect today, prohibiting employers from hiring, firing or determining promotions based on genetic makeup.

Starting Dec. 7, group health insurers will not be allowed to consider a person’s genetics — such as predisposition for Parkinson’s disease — to set insurance rates or deny coverage.

Not since the Americans with Disabilities Act of 1990 has the federal government implemented such far-reaching workplace protections.

“No one should be denied a job or the right to be treated fairly in the workplace based on fears that he or she may develop some condition in the future,” said Stuart Ishimaru, acting chairman of the Equal Employment Opportunity Commission.