Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Based Genome Editing in Inherited Cardiovascular Diseases: Therapeutic Advances, Emerging Editing Platforms, and Translational Challenges

Figures

• 

  Figure 1. Key steps involved in CRISPR-Cas9 gene editing. Figure 1 shows the stepwise process of genome editing using CRISPR-Cas9. The first step is that the sgRNA enables the Cas9 enzyme to bind to the target DNA sequence adjacent to the PAM, allowing the system to locate the specific target. After binding, the HNH and RuvC domains of Cas9 cleave the DNA and produce a double-strand break (DSB). This break is then repaired by the cell through two main mechanisms: NHEJ and HDR. NHEJ is a rapid process but often leads to insertions or deletions (indels) that can disrupt gene function and allow gene knockdown. HDR can use a homologous donor template to precisely repair or insert a piece of genetic material. This pathway is less efficient, however, and is primarily active during the S and G₂ phases of the cell cycle. Together, these repair mechanisms constitute the molecular basis of CRISPR-Cas9-mediated therapeutic genome editing in precision medicine. This figure was created by the authors using Adobe Illustrator v25.4.1. Cas9: CRISPR-associated protein 9; RNA: Ribonucleic acid; RuvC: RuvC nuclease domain; HNH: HNH nuclease domain; PAM: Protospacer-adjacent motif; sgRNA: Single-guide RNA;…

• 

  Figure 2. Overview of the evolution of CRISPR-based genome editing technologies. Conventional CRISPR-Cas9 causes double-strand DNA breaks that are repaired by NHEJ or HDR. Base editing enables precise single-base conversions without generating double-strand breaks and includes CBEs and ABEs. Prime editing extends the scope of editing to all types of point mutations, as well as small insertions and deletions, by combining a Cas9 nickase with a reverse transcriptase and a pegRNA. CRISPR-based transcriptional and epigenome editing utilizes catalytically inactive Cas9 (dCas9) linked to transcriptional repressors, activators, or epigenetic modifiers to control gene expression, enabling CRISPRi or CRISPRa without changing the underlying DNA sequence. This figure was created by the authors using Adobe Illustrator v25.4.1. ABE: Adenine base editor; CBE: Cytosine base editor; CRISPR: Clustered regularly interspaced short palindromic repeats; CRISPRa: CRISPR activation; CRISPRi: CRISPR interference; Cas9: CRISPR-associated protein 9; dCas9: Catalytically dead Cas9; HDR: Homology-directed repair; NHEJ: Non-homologous end joining; nCas9: Cas9 nickase; PAM: Protospacer-adjacent motif; PBS:…

• 

  Figure 3. Stepwise workflow of CRISPR-Cas9-based therapeutic development for inherited cardiovascular diseases. This figure illustrates the workflow from patient identification to therapeutic outcomes in CRISPR-mediated cardiovascular gene editing. The process begins with the identification of patients or families with inherited cardiovascular diseases such as HCM, DCM, FH, and channelopathies. This is followed by genetic screening to identify pathogenic mutations. A CRISPR strategy specific to the target mutation is then designed. Delivery vectors such as AAVs or LNPs are subsequently developed to facilitate targeted delivery through in vivo or ex vivo approaches. The next steps are to evaluate gene-editing efficacy, assess cardiac function, and conduct safety testing. The intended outcomes are disease amelioration and clinical benefit. This figure was created by the authors using Adobe Illustrator v25.4.1. gRNA: Guide RNA; AAV: Adeno-associated virus; LNP: Lipid nanoparticle; HCM: Hypertrophic cardiomyopathy; DCM: Dilated cardiomyopathy; FH: Familial hypercholesterolemia.