Among the 138 SPK patients who received valganciclovir prophylaxis, leukopenia was detected in 63 (46%), G-CSF was used to treat neutropenia in 16 (12%), mycophenolate dose was adjusted in 34 (25%), and valganciclovir had to be discontinued prematurely in 28 (20%) patients (Table 2). The gene discussed is CSF3; the disease is Decreased total leukocyte count.