The enormous marble hall of the Organization of American States Saturday night was packed with dinner tables decorated with flowers. Roses were prominent in the floral arrays, in memory of a child who could not pronounce the name of the disease that killed him. The occasion was the second annual children's ball of the Cystic Fibrosis Foundation, and it raised $150,000 to combat a disease that kills more children each year than diabetes and muscular dystrophy combined.

Jondra McFarlane, wife of national security adviser Robert C. McFarlane and chairman of the ball, got the roses from Brookside Garden, the American Horticultural Society and the Bon-Air Gardens by telling them the story of a young CF victim who called his disease "65 roses." Since then, roses have been a symbol for the CF Foundation.

"There are a lot of causes to be joined," McFarlane said, "but this one is compelling because it affects children who are not old enough to organize, fund-raise and legislate. It's especially exciting now, because we have the feeling that we are close to some kind of breakthrough in the research."

Besides the current national security adviser, the ball was attended by his two immediate predecessors, William P. Clark, who is now secretary of the interior, and Alexander Haig. Under the honorary chairmanship of Nancy Reagan, the ball drew a fair number of administration types, including Air Force Secretary Verne Orr, U.S. Trade Representative William Brock, FCC Chairman Mark Fowler and Office of Management and Budget Director David Stockman. The Democrats were represented by Rep. Tony Coelho of California and Rep. John Dingell of Michigan. Many of the $500-a-plate tables were occupied by executives of corporate sponsors such as AT&T, Boeing, McDonnell Douglas and U.S. Steel.

"The community has a wonderful sense of social responsibility," McFarlane said. "It is full of people who are very busy, but they will turn out for an event like this, and that makes you proud to live here."

Cystic fibrosis is a genetic disease that produces abnormal amounts of thick mucus, which interferes with breathing and digestion. It was first identified as a disease only in 1938, and it is estimated that one in 20 Americans are symptomless bearers of the still-unidentified gene that causes it. When two people who have the gene bear a child, there is a 25 percent chance that the child will have CF and a 50 percent chance that the child will carry the gene. Originally, the average life expectancy of children with CF was three to five years. Treatment of its effects has advanced to a stage where average life expectancy is now 21, but no cure and no permanent, effective means of control have been found, according to Robert Beall, the foundation's vice president for medical affairs. CF has killed about 65,000 children since it was identified and about 30,000 victims are living today, with 2,000 new cases diagnosed each year.

Still, there was an air of optimism at the CF ball. Beall said that recent advances in genetics have given researchers a hope of identifying the gene, and that could lead to more effective means of control and prevention. "My doctor tells me that the answers to cystic fibrosis are just around the corner," a brochure prepared by the foundation quotes a young victim as saying. "I sure hope they find the right corner in time."

The working leadership of the CF Foundation is made up not of professional fundraisers, but of a president and immediate past president both working full-time because they have children still alive but threatened with the disease.

Robert Dresing's son is 17, and Dresing has been involved with the foundation since his son's condition was diagnosed. "He's doing fine," Dresing said. "I want him to go on doing fine for a long time. I think he has a chance to survive -- that he's one of the fortunate ones who will benefit from the research going on today." A few years ago Dresing sold his business to a large conglomerate, but rather than retiring he has become the president of the foundation.

His predecessor, Doris Tulcin, has a daughter who has survived with CF for a remarkable 31 years. Tulcin is now in charge of fundraising for a new $15 million research and development program. She says that $15 million is "a minimum," but she hopes "we can lick this disease in five years." An event such as the annual ball, besides raising funds, helps to "identify people who are really interested," she said. "Out of this room tonight, maybe we'll identify five or six people."

The secret of her fund raising, Tulcin said, is awareness that "people don't give to causes, they give to people." And the thought that keeps her going is, "You only have to lick a disease once."

CF vice president Frank Deford is probably the best-known officer of the foundation. A senior writer for Sports Illustrated, he is the author of a half-dozen books of fiction and nonfiction, including "Alex: The Life of a Child," about his daughter, who died of CF at age 8, four years ago. "There are congressmen here," said Deford. "The next time they hear the words 'cystic fibrosis,' they'll know what it's about. Recent scientific advances have given us more hope -- I just met some people who have a 3-year-old daughter, and I told them, 'My daughter is dead, but I think your daughter is going to live.' "

He recalled a boy who appeared with him on a television show last year. "He asked me, 'Why are you here? Your daughter is dead,' and I just dissolved. Then I told him, 'I would disgrace the memory of my daughter if I cut and ran now.' Two months later, that boy was dead. He was dying when he talked to me, and he knew it. I guess the legacy of Alex's death is that her father and mother are working on this. If we ever lick this thing, we'll raise a toast in her honor.

"She served a purpose," Deford said. "She helped to show that kids aren't supposed to die."