The EEOC has published the regulations employers need to implement GINA - the Genetic Information Non-Discrimination Act. This is a new law that prohibits descrimination based on your genetic likilhood to develop certian medical problems. HPS'ers often get confused by this act. It does not address issues of descrimination based on current medical problems or disabilities - it only protects you from descrimination based on the likihood you'll have problems in the future based on your genetics.
Here's a link to the new EEOC rules for employers. It's not a bad idea to get to know them yourself so you're well informed about your rights.