Cystic fibrosis--problems and prospects [editorial].

Cystic fibrosis, an autosomal recessive trait, is the most common hereditary lethal 
condition among Caucasians, approximating a prevalence of 1 per 2500 births 
with a carrier frequency of 1:25 in populations originating from West 
Europe. The markedly elevated frequency of CF in a considerable proportion 
of the human race presents a genetic enigma for which several 
solutions have been proposed. Genetic heterogeneity, heterozygote advantage, reduced penetrance, genetic 
drift, and linkage or epistasis are discussed. The basic defect in 
CF and its fundamental biochemical and physiological ramifications are unknown. 