Suffers from severehypoglycemia after prolonged fasting

You are a doctor treating a patient who suffers from severehypoglycemia after prolonged (>24 hr.) fasting. Glucose is converted to lactatenormally in the patient’s liver. You administer glucogon and find that bloodglucose increases normally (the patient was in the well-fed state prior to thistest). The patient’s liver shows normal activities of pyruvate carboxylase and PEPcarboxykinase. Which enzyme may show a genetic defect that accounts for these findings?Briefly explain your reasoning.