Waardenburg syndrome type 1 (WS1) is a hereditary disease mainly characterized by sensorineural hearing loss, dystopia canthorum, and pigmentary defects. To elucidate molecular mechanisms underlying PAX3-associated hearing loss, we developed inner ear organoids model using induced pluripotent stem cells (iPSCs) derived from WS1 patient and healthy individual. Our results revealed a significant reduction in the size of inner ear organoids, accompanied by an increased level of apoptosis in organoids derived from WS1 patient-iPSCs carrying PAX3 c.214A > G. Transcriptome profiling analysis by RNA-seq indicated that inner ear organoids from WS1 patients were associated with suppression of inner ear development and WNT signaling pathway. Furthermore, the upregulation of the WNT1/β-catenin pathway which was achieved through the correction of PAX3 isogenic mutant iPSCs using CRISPR/Cas9, contributed to an increased size of inner ear organoids and a reduction in apoptosis. Together, our results provide insight into the underlying mechanisms of hearing loss in WS.

瓦登堡综合征1型（WS1）是一种遗传性疾病，主要特征为感音神经性听力损失、内眦异位和色素缺陷。为了阐明PAX3相关听力损失的分子机制，我们使用来自 WS1 患者和健康个体的诱导多能干细胞 (iPSC) 开发了内耳类器官模型。我们的结果显示，内耳类器官的大小显着减小，同时来自携带PAX3 c.214A > G 的 WS1 患者 iPSC 的类器官的细胞凋亡水平增加。通过 RNA-seq 进行的转录组分析表明，内耳类器官WS1 患者的 WNT 信号通路与内耳发育和 WNT 信号通路的抑制有关。此外，通过使用 CRISPR/Cas9 校正PAX3同基因突变 iPSC 实现的 WNT1/β-catenin 通路上调，有助于内耳类器官大小的增加和细胞凋亡的减少。总之，我们的结果提供了对 WS 听力损失的潜在机制的深入了解。