You will be given a definition of a task first, then some input of the task.
In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.

 Fulminant hepatic failure in these cases could be characterized by : ( 1 ) rapid decrease in serum alanine transaminase ( ALT ) level after discontinuation of ecarazine , ( 2 ) prolonged jaundice despite discontinuation of ecarazine , ( 3 ) high incidence of anti - nuclear antibody ( ANA ) ( 57 % ) , and ( 4 ) histological findings of extensive hepatocellular necrosis ranging from bridging necrosis to massive necrosis .
Output:
serum alanine transaminase