Referring to his recent graduation from graduate school, Kuo wrote: "For the last three months, I have lived a life where I have been unprecedently happy, where all opportunity seems to open up itself before me, only to be shut down again quietly, randomly. Therefore, I am sad-not angry, just sad."

But, never one to dwell on the negative, Kuo added, "Of course, now that this is said, there are things to do."

At first, Kuo, whom friends describe as private, was hesitant to use his name and image in publicity. But he soon conceded to demands that they be used to generate public support.

James C. Kuo, Alan's father, said yesterday from Berkeley that the past two years have been "difficult and heartbreaking."

"I have to be optimistic, but it's very difficult because the antigen is very hard to find and hopefully, we'll find one soon," Mr. Kuo said.

He said Alan recently moved from the chronic stage of leukemia to its acute stage, which means the patient only has one or two months left to live.

Mr. Kuo said Alan recently underwent chemotherapy to treat his cancer cells but that the chemotherapy was only a short term solution. He said Alan was undergoing more chemotherapy later this week.

Mr. Kuo said it has been so difficult to find a match because one of Alan's antigens is so unique.

"Alan's antigen is very special and he has a difficult one" to match, Mr. Kuo said. "The number of new donors has not increased fast enough, although it has increased by one-third or one-half. We probably need a pool of a million donors of the same race."

In order to be a successful match, all six antigens on the donor's human leukocyte antibody (HLA) need to match Alan's antigens.

Mr. Kuo said there are two people so far who have been found to possess five of Alan's six antigens.

One match is a white woman who is a mother and the other is a young Japanese-American male, Mr. Kuo said.

Mr. Kuo said it was unusual for a Caucasian person to possess such a good match to Alan's genetic make-up but surmised that she probably had some Asian blood.

However, Ho said he was told by Kuo's doctor, Hope Rugo, a hematologist and oncologist with UCSF, that if Kuo receives an imperfect match there will be an 80 percent chance his body will reject the marrow.

Therefore, Kuo is still holding out for a perfect match, which would reduce the chance of rejection to 20 to 30 percent, Ho said. Dr. Rugo could not be reached for comment yesterday.