Background: Geographic and ethnic variations contribute to the variability of incidences among CML registries. Reliable data concerning response rates to therapy in Arab nations is lacking. CML management areas are not in line with the current recommendations, due to sub-optimal timing of treatment decisions, under monitoring, and lack of molecular techniques or TKIs. Median age differs between cancer registries and clinical trials by 10-20 years. Objectives: Assessing the incidence of different BCR-ABL transcript types, among young Egyptian CML patients in different centers in Egypt to assess the impact of ethnic and demographic variables on disease outcome, particularly according to gender and age. And, the relationships of different transcript types with the disease characteristics and response to treatment type. Patients and Methods: This study was conducted on 93 patients with CML from databases of Ain Shams University CML clinic and Hematology and Bone Marrow units, databases of Laboratories testing BCR-ABL for diagnostic purposes & Other contributing medical centers, (51 males, 42 females) with age range (18 years to < 50 years) after obtaining a written informed consent. Results: Patients were divided into 3 groups according to BCR-ABL transcript type. 36 patients had b2-a2, 45 patients had b3-a2 and 12 patients had both. (38.7%, 48.4% and 12.9% respectively). Risk stratification according to Sokal score was done. 30 patients were of low risk, 60 patients were of intermediate risk and 3 patients were of high risk (32%, 65% and 3% respectively). Mean Sokal score in patients with b2-a2 was 0.79, in patients with b3-a2 was 0.88 and in patients with both was 0.83.Risk stratification according to Hasford score was done. 48 patients were of low risk, 45 patients were of intermediate risk and there were no high risk patients (52%, 48% and 0% respectively).Mean Hasford score in patients with b2-a2 was 652.9, in patients with b3-a2 was 831.9 and in patients with both was 914.4.All patients had low EUTOS risk score. Mean EUTOS score in patients with b2-a2 was 41.9, in patients with b3-a2 was 54.7 and in patients with both was 53.5. All patients presented with splenomegaly, the mean size of spleen was 18 cm at diagnosis. All patients presented with leukocytosis, mean basophilic count was (3×103/µL), mean eosinophilic count was (6.35×103/µL), mean platelet count was (364.4×103/µL).Patients’ BCR-ABL levels were measured by PCR at 5 time points: Initially, at 3 months, at 6 months, at 9 months and at 12 months. Patients with b2-a2 had higher PCR levels than the other 2 groups initially and at 3 months. The difference was statistically significant. Initially, PCR was higher in patients with b2-a2 compared to patients with b3-a2 and to patients with both (p=0.001 and p=0.011 respectively).At 3 months, PCR was higher in patients with b2-a2 compared to patients with b3-a2 (p=0.018).All other differences were not statistically significant. Conclusion: Patients with b2-a2 had higher PCR levels than the other 2 groups initially and at 3 months. There was no difference at 6 monthes & later.