Crystalline retinopathy is a kind of single gene hereditary disease which can cause serious harm to visual health. Another significant feature of BCD is that it has a significantly higher incidence in East Asian populations than in other populations.

Although BCD is a kind of serious blinding genetic eye disease, compared with "star genetic disease" which is highly concerned by some western media, the basic and clinical research on BCD is relatively deficient. So far, there is still a lack of effective animal models of BCD, leading to the inability to further understand the influencing factors of BCD disease course.On the other hand, there's no way to test potential treatments. Eighty years after the Italian doctor G.B. Bietti first observed and named the disease, THERE is still no cure for BCD.

CYP4V2 is the body's version of the omega-hydrogenase gene, which plays a role in many metabolic pathways. The gene CYP4V2, inherited from both parents, mutates simultaneously, causing BCD to develop. Patients with BCD had significantly abnormal lipid levels compared to normal levels. By knocking out the entire Cyp4v3 loci in mice, the team at the Institute of Zoology, Chinese Academy of Sciences, successfully constructed a mouse model with Cyp4v3 deletion. Further studies found that mice with Cyp4v3 deletion fed high-fat diets exhibited a dual BCD disease phenotype with fundus crystallization and impaired vision function. As one of the six nutrients, fat is unavoidable in our diet. The above results indicate that high lipid level is not only an abnormal manifestation of BCD disease, but also a risk factor for accelerating the progression of BCD disease. This suggests that controlling daily fat intake may be an important means to improve BCD disease care and delay disease progression.

Gene therapy is a new treatment method to introduce foreign genes into cells to correct or compensate the diseases caused by gene defects or abnormal gene expression, which has great potential in the treatment of inherited diseases. The team injected human CYP4V2 gene packaged with adeno-associated virus into mouse models of Cyp4v3 knockout on high-fat diet to further verify the applicability of gene therapy to BCD. Mice treated with gene therapy were found to have significantly increased fundus thickness and improved visual function. These results are the first to demonstrate the efficacy of gene therapy for BCD in a live animal model.

Time：2020.06.05

Source: http://www.cas.cn/syky/202006/t20200603_4748790.shtml