Somatic genome editing with CRISPR/Cas9 generates and corrects a metabolic disease

TLDR

CRISPR/Cas9 germline editing has accelerated mouse model generation, yet many metabolic disease models still rely on laborious germline targeting and must avoid developmental phenotypes. The study aims to overcome these limitations by generating somatic liver mutations with CRISPR/Cas9 to model metabolic disorders. They used AAV‑CRISPR to target hepatic Ldlr, whose loss causes severe hypercholesterolemia and atherosclerosis, as a proof‑of‑principle. Hepatic Ldlr disruption via AAV‑CRISPR induced severe hypercholesterolemia and atherosclerosis, while simultaneous Apob disruption prevented disease by inhibiting hepatic LDL production, illustrating that somatic genome editing can model metabolic disorders and may be applied to other challenging diseases.

Abstract

Abstract Germline manipulation using CRISPR/Cas9 genome editing has dramatically accelerated the generation of new mouse models. Nonetheless, many metabolic disease models still depend upon laborious germline targeting, and are further complicated by the need to avoid developmental phenotypes. We sought to address these experimental limitations by generating somatic mutations in the adult liver using CRISPR/Cas9, as a new strategy to model metabolic disorders. As proof-of-principle, we targeted the low-density lipoprotein receptor ( Ldlr ), which when deleted, leads to severe hypercholesterolemia and atherosclerosis. Here we show that hepatic disruption of Ldlr with AAV-CRISPR results in severe hypercholesterolemia and atherosclerosis. We further demonstrate that co-disruption of Apob , whose germline loss is embryonically lethal, completely prevented disease through compensatory inhibition of hepatic LDL production. This new concept of metabolic disease modeling by somatic genome editing could be applied to many other systemic as well as liver-restricted disorders which are difficult to study by germline manipulation.