Acute neonatal illness was defined as having one of the following symptoms: icterus, encephalopathy (decreased consciousness with or without neurological symptoms), bleeding diathesis (abnormal prothrombin time (PT) and/or activated partial thromboplastin time (APTT)), infection signs or hypoglycemia (glucose < 2.6 mmol/L). The gene discussed is F2; the disease is Hypoglycemia.