The World Health Organization has named a new allele identified by Chinese scientists that will hopefully enhance the success rates of bone marrow transplants for leukemia patients.

The allele, HLA-A*110104, was identified recently by immunologists with the Beijing-based No. 307 Hospital of the Chinese People's Liberation Army, while matching hematogenic stem cells for a leukemia patient from the northern Shanxi Province.

The team of experts, headed by Xi Yongzhi, found an unknown gene in the patient's younger brother who was the potential bone marrow donor. Seeing that the gene did not exist in the international gene bank, Xi and his colleagues paid a visit to the patient's hometown to take blood samples from his father, and detected the same gene.

Shortly after their Shanxi tour, the immunologists found the newly discovered gene again in a patient from the eastern Anhui Province. Laboratory work later found the same gene in blood samples from the patient's parents and grandparents, too, said Xi.

WHO's HLA naming committee has named the allele and published the discovery in several academic journals, according to Xi.

The new allele will match more adequate types of bone marrow for leukemia and other fatal blood disease sufferers, for whom the best therapy available so far is bone marrow transplant, said Xi.

HLA, or human leucocyte antigen, is a kind of antigen of the white blood cells. There are three types of HLA -- A, B and C.

Doctors rely on HLA antigen system that gauges how well donated tissue matches the patient's immune system. A perfect match, usually from a relative, is best. The more HLA mismatches there are, the greater the risk of rejection.

This has made matching more difficult in China, the land of only child where leukemia patients are increasing by 40,000 a year and more than 4 million patients are waiting for bone marrow transplants.

The results of the Chinese scientists' research may also help organ transplant patients find ideal donors and help anthropologists find out more about the migration of different ethnic groups in history, according to Xi.

A*110104 is not the only HLA allele identified by Chinese scientists. A group of researchers in southern boom city of Shenzhen discovered one new allele in 2001 and another two in 2002. In 2003, scientists identified a new allele named HLA-B*5516 in a girl in southwest China's Sichuan Province. In October 2004, transfusion experts in east China's Zhejiang Province identified two new alleles: HLA-B*5614 and HLA-B*5136.

About 80 percent of the 1,013 known alleles of HLA-A, B, DRB1 were discovered by American scientists. Identification of unknown alleles is a hotspot for worldwide scientists and the competition is extremely high.

Source: Xinhua