Project description:The most common form of genetic heart disease is hypertrophic cardiomyopathy (HCM), which is caused by mutations in cardiac sarcomeric genes and leads to abnormal heart muscle thickening. Complications of HCM include heart failure, arrhythmia, and sudden cardiac death. The dominant-negative c.1208 G>A (p.R403Q) mutation in b-myosin (MYH7) is a common and well-studied mutation that leads to increased cardiac contractility and HCM onset. Here we identify an adenine base editor (ABE) and single-guide RNA system that can efficiently correct this human pathogenic mutation with minimal off-target and bystander editing. We show that delivery of base editing components rescues pathological manifestations of HCM in iPSC-cardiomyocytes derived from HCM patients and in a humanized mouse model of HCM. Our findings demonstrate the use of base editing to treat inherited cardiac diseases and prompt the further development of ABE-based therapies to correct a variety of monogenic mutations causing cardiac disease.
2022-10-25 | GSE201755 | GEO
Project description:In vivo adenine base editing in an adult mouse model of tyrosinemia
| PRJNA513076 | ENA
Project description:In vivo postnatal base editing rescues hearing in a mouse model of recessive deafness
Project description:The majority of known pathogenic point mutations in the human genome are C•G to T•A substitutions. Adenine base editors (ABEs), comprised of nuclease-impaired Cas9 fused to adenine deaminases, enable direct repair of these mutations, making them promising tools for precision in vivo genome editing therapies. However, prior to application in patients, thorough safety and efficacy studies in relevant model organisms are needed. Here, we apply adenine base editing in vivo in the liver of mice and cynomolgus macaques to install a splice site mutation in PCSK9 and reduce blood low-density lipoprotein (LDL) levels, a well-known risk factor for cardiovascular disease. Intravenous delivery of ABE-encoding mRNA and a locus-specific single guide (sg)RNA utilizing lipid nanoparticle (LNP) technology induce up to 67% editing in the liver of mice and up to 34% editing in the liver of macaques, leading to a reduction of plasma PCSK9 and LDL levels. We observed rapid clearance of ABE mRNA after LNP-mediated delivery, and neither sgRNA-dependent nor sgRNA-independent off-target mutations are detected in genomic DNA. Together, our findings support safety and feasibility of adenine base editing to treat patients with monogenetic liver diseases.
Project description:The majority of known pathogenic point mutations in the human genome are C•G to T•A substitutions. Adenine base editors (ABEs), comprised of nuclease-impaired Cas9 fused to adenine deaminases, enable direct repair of these mutations, making them promising tools for precision in vivo genome editing therapies. However, prior to application in patients, thorough safety and efficacy studies in relevant model organisms are needed. Here, we apply adenine base editing in vivo in the liver of mice and cynomolgus macaques to install a splice site mutation in PCSK9 and reduce blood low-density lipoprotein (LDL) levels, a well-known risk factor for cardiovascular disease. Intravenous delivery of ABE-encoding mRNA and a locus-specific single guide (sg)RNA utilizing lipid nanoparticle (LNP) technology induce up to 67% editing in the liver of mice and up to 34% editing in the liver of macaques, leading to a reduction of plasma PCSK9 and LDL levels. We observed rapid clearance of ABE mRNA after LNP-mediated delivery, and neither sgRNA-dependent nor sgRNA-independent off-target mutations are detected in genomic DNA. Together, our findings support safety and feasibility of adenine base editing to treat patients with monogenetic liver diseases.