KANSAS CITY, Mo. (AP) — A dispute over a gay student's efforts to donate blood has divided students at a central Kansas high school and prompted talk of a letter-writing campaign against what some consider a discriminatory policy.

The controversy started last fall, after Josh Turner, a student at Winfield High School, was told by representatives from the American Red Cross that he could not donate blood because he was a gay male. When the Red Cross returned Wednesday for another blood drive, some students who supported Turner protested by wearing rainbow patches, a common symbol of gay pride.

Other students who supported the blood drive wore straight pride patches, which showed a picture of a man and woman holding hands. They also printed papers saying gays were not allowed and others with a slash through the word gay.

The controversy prompted school officials to invite students to an assembly to discuss the issue, said Superintendent Marvin Estes.

Estes said the point of the meeting was to explain that Turner's rejection was based on a U.S. Food and Drug Administration policy that the Red Cross is required to follow.

"This is not a gay-straight issue, although that was the way it was being played out," Estes said. "The student was denied because of the rules in place to screen people who want to give blood."

A man who answered the phone at Turner's home Thursday said Turner wasn't home. But a group of about 35 students who met Wednesday after school told The Winfield Daily Courier that they planned to write the FDA, the Red Cross, the school district and state and federal lawmakers about the policy.

Estes said he hoped that Wednesday's meeting, which involved about 250 of the school's 750 students, helped educate the students and calm a divisive situation.

"I'm not going to say that everyone went away from the meeting with a complete, clear understanding of the issues," Estes said. "It was a spirited discussion and we had some kids that are very passionate on both sides of the issue.

"We hope they understand that it wasn't discrimination, it was the rule. If they want to fight the rule, that's fine."

The FDA policy excludes males who acknowledge having sex with another male even once since 1977 because they are at an increased risk of carrying HIV, hepatitis and other infections that can be transmitted through transfusions. While acknowledging that improved testing for HIV and hepatitis has greatly reduced the risk of transmitting the diseases, the FDA says it's first priority is to protect the safety of the nation's blood supply.

"FDA scientists continue to monitor the scientific literature and to consult with (other experts," according to the FDA Web site. "FDA will continue to publicly revisit the current deferral policy as new information becomes available."

The American Red Cross and other blood centers often are caught in the middle of disputes over the policy on gay men, said Darren Irby, a spokesman for the organization. The American Red Cross, the American Association of Blood Banks and America's Blood Centers have encouraged the FDA to modify it's policy, he said.

"We're disappointed that the changes haven't been made," Irby said. "We'll continue to work with (other groups) to really press for the donor deferral policies to be fair and consistent based on scientific evidence. Everyone's ultimate goal is to protect the blood supply from harm."