Landmark legislation banning discrimination based on genetic information moved within steps of enactment Thursday.

The bill, which President Bush is expected to sign, passed the House by 414-1, one week after the Senate passed it by 95-0. The House adopted a resolution correcting a technical glitch, and the Senate was expected to follow suit before the measure is enrolled and sent to the White House.

Chief sponsor Louise Slaughter, D-N.Y., who first introduced the legislation 13 years ago, told the House Thursday, “I honestly believe that this piece of legislation and what we have done here is the most important thing I have done in my life and we have done here in Congress.”

The measure would prohibit insurers from basing enrollment or premium decisions on the results of genetic tests, and would bar employers from using such data in hiring, assignment, promotion or firing decisions.

Health experts and lawmakers say enactment of the discrimination ban should ease the fears of people who avoid genetic tests or enrollment in clinical trials of new medicines because they fear the results will be used against them.

“Studies show that 85 percent of Americans fear that employers will use genetic information to discriminate,” said Rep. Judy Biggert , R-Ill., who along with Slaughter has been the leading House proponent for the bill. “The dean of a prominent university in Massachusetts told me that fear of genetic discrimination is hindering clinical trials, slowing the development of lifesaving techniques.”

Genetic testing can identify predisposition to a wide range of diseases, allowing individuals to get regular checkups to catch problems early, when treatment is most likely to succeed.

Liability concerns of employers and the White House held up the bill until the Senate this month made changes to strengthen a “firewall” between the employer and insurer provisions of the legislation, so that businesses couldn’t be hit with penalties under both sections.