Detection of cystic fibrosis homozygotes and heterozygotes with plasma.

Evidence is accumulating which indicates that the basic defect in cystic fibrosis 
interferes with the formation of recognition markers on hydrolytic enzymes. As 
a result these hydrolases leak into the extracellular space and some 
of them display abnormal thermolabilities. By heat inactivation of plasma alpha-mannosidase 
at 41 degrees C and plasma phosphatase at 36.5 degrees C, 
both enzymes being assayed at pH 5.4, it is possible to 
differentiate normal people from cystic fibrosis carriers and patients. 