THE INDENTIFICATION of the cystic fibrosis (CF) gene earlier this month culminated one of the most concerted and competitive efforts in the history of medical genetics.
Cystic fibrosis' high incidence (one in 2000 births in the United States), severity, and resistance to prenatal diagnosis has made its gene an especially attractive prey for molecular biologists and geneticists. The race to find the gene began, for all practical purposes, in 1980 with the discovery that restriction fragment length polymorphisms (RFLPs), stretches of DNA that vary among people, could serve as diagnostic markers if they were close enough to a disease gene to be inherited with the gene most of the time. By analyzing the DNA from several members of an affected family, it was often possible to tell which RFLP haplotype signaled the disease in that family.
Lap-Chee Tsui, PhD, became involved in the quest to find RFLPs associated with the