As Robin Roberts waits for a bone marrow transplant, the “Good Morning America” anchor’s illness is helping others who need treatment.

The national bone marrow donation registry reported Tuesday the rate of new registrants has more than doubled since Roberts announced June 11 she has MDS, a blood and bone marrow disease.

She helped supervise a registry drive at ABC News headquarters in Manhattan, where ABC News President Ben Sherwood and colleagues George Stephanopoulos and Lara Spencer were tested.

Roberts, who will receive a bone marrow transplant from her sister, said her mother told her to “turn a mess into a message.”

“When I received this latest disappointment I did not know what the message would be,” she said, “and now I do.”

Jeffrey Chell, CEO of Be The Match, said some 15,000 people had registered since Roberts announced her diagnosis. That’s 11,200 more than the registry would normally receive in that period. Of those new people, some 60 to 70 will be judged a good match and have some of their marrow used in a transplant.

Roberts’ effort to publicize the bone marrow registry is reminiscent of Katie Couric at NBC’s “Today” show in the 1990s. She urged people to be tested for the same type of cancer that her husband had suffered and died from.