Abstract: 【Abstract】  β-thalassaemia is a genetic disease of human β-globin (HBB) gene mutation, there is no cure possible, leading to the disorder of globin expression. CRISPR/Cas system, as the acquired immune system of bacteria and archaea, can transform the genome of many organisms at present. CRISPR/Cas9 systems is widely used for the advantages of easy programming, inexpensive construction, high specificity and multiplexed genome editing. The latest study using CRISPR/Cas9 systems combined with induced pluripotent stem cells to correct human HBB has become possible，meanwhile produces normal hemoglobin to reduce the symptom of patients with β-thalassaemia. The outcome will be a tremendous disasters, if off-target effect occured in human, that′s scientist worried about. To increase the safety of CRISPR/Cas9 gene editing, the latest research avoid the off-targets effect by increasing the specificity of CRISPR resection and controlling the Cas9 effectively. We reviewed the latest researches on the CRISPR/Cas9 systems and deal with off target effects.
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Key words: beta-thalassemia, Genes, Therapy, CRISPR/Cas