The gamma-GT (gamma-glutamyl transferase), also known as gamma-glutamyl transpeptidase, are proteins, specifically enzymes
, being naturally produced by the body, mainly in the liver
. The concentration of gamma-GT in the blood
is usually less than 60 international units per liter of blood, but it can be increased in certain diseases. The most common cause of this increase is chronic alcoholism
. Other diseases such as liver damage, diabetes
, medications, or certain infections
may also increase the levels.