HLA-DQB1 and Absence of circulating granulocytes: We found independent support for association of HLA-DQB1 6672G>C (OR=15.6, 95% CI: 1.6–151.4, P=0.015), replicating previous reports of association with clozapine-induced agranulocytosis.17 The association strengthened when considering only those with ANC below ⩽1000 mm−3 (OR=38.1, 95% CI: 3.4–430.9, P=0.0079).