The Fanconi anemia genes.

Until recently, it had been thought that Fanconi anemia patients were distributed into five complementation groups. However, evidence now points to the existence of three new complementation groups, making the genetic basis of the disease more complicated than anticipated. Also, during the past year, the cloning of a second Fanconi anemia gene by both functional complementation and positional cloning has accelerated research of this disease. Although two genes of the eight characterized complementation groups have now been cloned, the function of their gene products still needs to be identified.