Genetic variants established as independent risk factors for early neutropenia were GSTM3 rs3814309 genotype CC (OR 3.12; 1.29–7.52; p = 0.01), ABCB1 rs17064 variant AT (OR 3.52; 1.29–9.56; p = 0.013), ERCC1 rs1046282 genotype CC (OR 5.88; 1.50–22.97; p = 0.01), and ALDH5A1 rs1054899 allele C (OR 1.66; 1.0–2.75; p = 0.046) (Table 3). Here, ABCB1 is linked to neutropenia.