DNAI3 (dynein axonemal intermediate chain 3) functions as a critical component of the axonemal dynein complex, playing dual roles in ciliary function and cell migration regulation. As part of the inner dynein arm, DNAI3 contributes to axonemal dynein assembly and cilium movement 1. Beyond its structural role, DNAI3 acts as a negative regulator of cell migration and metastasis by inhibiting Arp2/3 complex-mediated actin polymerization downstream of p53/TP53 signaling. Clinically, DNAI3 variants associate with multiple disease states. In primary ciliary dyskinesia (PCD), mutations in related genes like DNAI2 cause outer dynein arm defects and chr1 respiratory infections, suggesting DNAI3's importance in ciliary integrity 2. DNAI3 variants show suggestive genome-wide associations with susceptibility to upper urinary tract infections in females 3. Additionally, DNAI3 was identified among 15 genes causally associated with lung adenocarcinoma through microbiota-driven pathways 4, and DNAI3 expression is regulated by PTEN-NR2F1 signaling in EGFR-mutant lung cancer, affecting bronchial cell hyperplasia 5. DNAI3's clinical significance extends to potential involvement in osteogenesis of dental mesenchymal stem cells. These diverse associations underscore DNAI3's importance in maintaining ciliary function while regulating cellular motility processes relevant to cancer progression and infectious disease susceptibility.