• Adult hemoglobin predominantly consists of Hemoglobin A, which is composed of two α-chains and two β-chains (α2β2). An imbalance between these α- and β-chains can result in the clinical manifestations of Thalassemia. This condition can be categorized into two primary types: α-thalassemia and β-thalassemia.
• Gene editing strategy:  The Hbb-bt and Hbb-bs genes were completely deleted in B-Hbb-bt KO, Hbb-bs KO mice. 
• Blood routine test: The complete blood count test results reveal that, in comparison to the wild-type C57BL/6N mice (+/+), there is a substantial decline in RBC, HGB, HCT, MCV, MCH and MCHC in heterozygous B-Hbb-bt KO, Hbb-bs KO mice (H/+). Conversely, these mice exhibit a significant increase in RDW, NRBC# and NRBC%.
• Blood smear test: The blood smear analysis results showed that the red blood cells of heterozygous B-Hbb-bt KO, Hbb-bs KO mice (H/+) were inconsistent in size, with an enlarged central pallor. There was also a significant presence of abnormal, fragmented and nucleated red blood cells.
• Application: This product is used for pharmacodynamics evaluation of thalassemia.

Blood smear analysis in wild-type C57BL/6N mice and heterozygous B-Hbb-bt KO, Hbb-bs KO mice. The blood smear analysis results showed that the red blood cells of heterozygous B-Hbb-bt KO, Hbb-bs KO mice (H/+) were inconsistent in size, with an enlarged central pallor. There was also a significant presence of abnormal, fragmented and nucleated red blood cells such as schistocytes (1), serrated erythrocytes (2), shadow cells or schistocytes (3), echinocytes or spiky/burr cells (4), target-like codocytes (5), spherocytes (6) and mouth-shaped stomatocytes (7).

The organs of Female wild-type C57BL/6N mice and heterozygous B-Hbb-bt KO, Hbb-bs KO mice (8-week-old, n=6). Compared with C57BL/6N mice, there was significant increase in spleen weight of heterozygous B-Hbb-bt KO, Hbb-bs KO mice. Values are expressed as mean ± SEM. Significance was determined by one-way ANOVA test.  *P < 0.05, **P < 0.01, ***p < 0.0001.