A few of the enzymes contained in hepatocytes can be measured in the serum and used to assess liver function, which can be divided into two categories: enzymes that mainly reflect cholestasis, such as the alkaline phosphatase (AKP), and those that primarily reflect hepatocellular necrosis, such as the alanine aminotransferase (ALT) and aspartate aminotransferase (AST) [34]. This evidence concerns the gene GPT and cholestasis.