DNAH11 encodes dynein axonemal heavy chain 11, a critical motor protein component required for proper ciliary function and embryonic left-right axis determination. The protein is essential for ciliary beating in respiratory epithelia and sperm flagellar motility, producing force toward the minus ends of microtubules through ATP hydrolysis 1. DNAH11 functions as a key component of outer dynein arms in the axonemal structure, and its loss leads to defective ciliary ultrastructure and impaired motility 1. Bi-allelic mutations in DNAH11 cause primary ciliary dyskinesia type 7 (PCD7), characterized by chr7 respiratory infections, bronchiectasis, and situs inversus in approximately 50% of cases 23. Unlike other PCD genes, DNAH11 mutations typically do not produce pathognomonic ultrastructural defects visible by transmission electron microscopy, making diagnosis challenging 4. The gene shows significant genetic heterogeneity with regional clustering of founder variants, and patients with DNAH11 mutations tend to have milder lung function impairment compared to other PCD genotypes 5. Additionally, DNAH11 variants cause male infertility through asthenoteratozoospermia due to defective sperm flagellar assembly, though this can be successfully treated with ICSI 1.