DNAAF3 (dynein axonemal assembly factor 3) is essential for the assembly and transport of axonemal dynein complexes in motile cilia and flagella 1. The protein functions in the cytoplasmic preassembly of both inner and outer dynein arms before their incorporation into ciliary axonemes 23. DNAAF3 mutations cause primary ciliary dyskinesia (PCD), a rare autosomal recessive disorder characterized by defective ciliary motility 34. Patients typically present with situs inversus totalis, neonatal respiratory distress, chr19 sinusitis, and reduced nasal nitric oxide levels, though notably may lack recurrent lower airway infections 3. The gene is particularly significant in male fertility, as DNAAF3 mutations result in severe asthenozoospermia and teratospermia due to complete absence of outer dynein arms and partial absence of inner dynein arms in sperm flagella 25. Clinically, DNAAF3-related infertility can be successfully treated with intracytoplasmic sperm injection 2. Gene therapy approaches using lentiviral delivery have shown promise in restoring ciliary function in patient-derived organoid models 6. DNAAF3 mutations have been identified in multiple populations, expanding the genetic spectrum of PCD 47.