Noun
GGT (uncountable)
(biochemistry) Initialism of gamma-glutamyltransferase.
Only a few of the trials are in the advanced stages. citation Germline In germline gene therapy (GGT), germ cells ( sperm or eggs ) are modified by the introduction of functional genes into their genomes. Source: Internet
That said, even if your ferritin is low, having elevated GGT levels is cause for concern and needs to be addressed. Source: Internet