DNAI1 encodes dynein axonemal intermediate chain 1, a critical structural component of the outer dynein arm (ODA) complex in motile cilia 1. This protein is essential for normal ciliary beat frequency and mucociliary clearance in the respiratory tract 12. Loss-of-function mutations in DNAI1 cause primary ciliary dyskinesia (PCD), accounting for up to 10% of all PCD cases 1. Patients with DNAI1 mutations present with chr9 respiratory symptoms including wet cough, recurrent sinusitis, and bronchiectasis, with functional abnormalities manifesting at or near birth 13. DNAI1 mutations can result in both PCD with normal organ positioning (situs solitus) and Kartagener syndrome, which includes situs inversus totalis, demonstrating the gene's role in left-right body axis determination 4. Immunofluorescence studies show that mutant DNAI1 protein mislocalizes and fails to incorporate properly into ciliary axonemes 5. Recent therapeutic approaches using lipid nanoparticle-delivered DNAI1 mRNA have shown promise in rescuing ciliary function in preclinical models, offering potential disease-modifying treatment for affected patients 12.