Antithrombin III deficiency was also associated with greater rates of progressive intracranial hemorrhage (21.1% [28 of 133] vs 6.3% [10 of 159]; P = .0003) and thrombocytopenia (24.8% [33 of 133] vs 5.0% [8 of 159]; P = 1.94 × 10−6). The gene discussed is SERPINC1; the disease is hyperinsulinemic hypoglycemia, familial, 4.