Treating Bietti crystalline dystrophy in a high-fat diet-exacerbated murine model using gene therapy

Lipid metabolic deficiencies are associated with many genetic disorders. Bietti crystalline dystrophy (BCD), a blindness-causing inherited disorder with changed lipid profiles, is more common in Chinese and Japanese than other populations. Our results reveal that mouse models lacking Cyp4v3 have less physiological and functional changes than those of BCD patients with this gene defect. After the administration of a high-fat diet (HFD), the occurrence of retinal lesions were both accelerated and aggregated in the Cyp4v3^-/- mouse models, implying that changed lipid levels were not only associated factors but also risk factors to BCD patients. Facilitated by the results, we found that the reduced electroretinography waveforms and retinal thickness observed in the HFD-induced mouse models were effectively recovered after subretinal delivery of a human CYP4V2 gene carried by an adeno-associated virus vector, which demonstrates the potential curability of BCD by gene therapy.