Its use is commonly associated with a number of side effects, such as hemorrhagic diathesis, neutropenia, leukopenia, thrombocytopenia, nausea, vomiting, abdominal pain, increased serum aspartate aminotransferase, increased serum alanine aminotransferase, decreased serum glucose, increased serum bilirubin, decreased serum phosphate and magnesium, fatigue, hypertension, diarrhea, anorexia, proteinuria, and hypothyroidism. The gene discussed is GPT; the disease is neutropenia.