Indeed, genetic background is distinct among different populations and our previous study had shown the genotype and allele frequencies of IFN-γ +874T/A were quite different among different regions and ethnicities.4 However, we noticed that there are 2 studies on CLL and 3 on CML in Caucasians, which may lead to negative results happened in the pooled analysis considering the dual role of IFN-γ +874T/A in CLL and CML. The gene discussed is IFNG; the disease is B-cell chronic lymphocytic leukemia.