Alternative Name(s): Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling

TUNEL

Test Description

The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay is a widely accepted in situ method for detecting nuclear DNA fragmentation, which occurs as one of the final stages of apoptosis. The assay relies on the ability of a terminal deoxynucleotidyl transferase (TdT) enzyme to incorporate labeled nucleotides onto free 3’-hydroxyl termini of DNA fragments. These labeled nucleotides are detected chromogenically to provide histological localization of apoptotic events.