HOXA9-positive CML was significantly associated with larger spleen size (15.9±2.5 cm vs. 5.4±3.2 cm, p<0.001), higher Sokal score (p<0.001), and BCR-ABL expression from the first round (p=0.004) (Table 2). This evidence concerns the gene ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive.