Our final finding adds to the growing evidence implicating HLA-DQB1 in clozapine-associated neutropenia, supporting the recently published CIAC study.6 There have been further reports implicating SNPs within HLA-DQB1,17, 41, 42 although these samples and those in CIAC are overlapping; thus, we believe we provide the first fully independent replication implicating this locus in clozapine-associated neutropenia/agranulocytosis. This evidence concerns the gene HLA-DQB1 and Absence of circulating granulocytes.