Table 1.

Summary of advantages and disadvantages of radioactive and fluorescence-based methodologies used to characterize the activity of LDLr variants.

Differences between Functional Validation Methodologies
Radioactivity	Fluorescence
Highly reproducible	Highly reproducible
Highly sensitive activity measurements	Highly sensitive activity measurements
Stable labeling	Stable labeling
Risk of exposure to radioisotopes	Nonradioisotopes used
Ethical considerations regarding waste elimination	In combination with CLSM allow LDLr classification
Noncompatible with CLSM

Disadvantages are shown in red.