Detection of cystic fibrosis heterozygotes using the zeta potential reduction method.

Parotid saliva samples from cystic fibrosis homozygotes, heterozygotes and normal individuals were tested by the zeta potential technique for secretion factor in a double-blind experiment. There was no overlap between zeta potential reduction of the control group and the cystic fibrosis test groups, indicating that the zeta potential test may be detecting a unique component in saliva of cystic fibrosis genotypes.