Identification of a Family with van der Hoeve's syndrome Harboring a Novel COL1A1 Mutation and Generation of Patient-Derived iPSC Lines and CRISPR/Cas9-Corrected Isogenic iPSCs

Abstract

Van der Hoeve's syndrome, also known as osteogenesis imperfecta (OI), is a genetic connective tissue disorder characterized by fragile, fracture-prone bone and hearing loss. The disease is caused by a gene mutation in one of the two type I collagen genes COL1A1 or COL1A2. In this study, we identified a novel frameshift mutation of the COL1A1 gene (c.1607delG) in a family with OI using whole-exome sequencing, bioinformatics analysis and Sanger sequencing. This mutation may lead to the deletion of a portion of exon 23 and the generation of a premature stop codon in the COL1A1 gene. To further investigate the impact of this mutation, we established two induced pluripotent stem cell (iPSC) lines from peripheral blood mononuclear cells (PBMC) of OI patients carrying a novel mutation in the COL1A1 gene. Using a CRISPR-based homology-directed repair strategy, we corrected the OI disease-causing COL1A1 novel mutations in iPSCs generated from an affected individual. Two OI patients' iPSCs and corrected OI-iPSC lines displayed a normal karyotype, morphology, pluripotency, and potential to differentiate into three germ layers. These findings demonstrate the potential of iPSCs derived from affected OI patients and corrected OI-iPSCs as a tool to study the pathophysiologic mechanisms of specific mutations. Overall, our results provide new insights into the genetic basis of Van der Hoeve's syndrome and highlight the potential of iPSC technology for disease modeling and therapeutic development.