Fig. 2

Structural variants in known PCD genes identified in unsolved patients in the Wessex PCD cohort. IGV screenshot showing heterozygous ~ 3.5 kb SV in DNAAF4 deleting exon 7 in case 8 in Table 3. This was found in trans with a stop gain variant in DNAAF4, providing a confirmed diagnosis for this patient. a IGV screenshot showing heterozygous ~ 9.5 kb SV in DNAH11 deleting exon 20 and 21 in case 9 in Table 3. This results in an in-frame deletion of amino acids 1256–1337 containing a coiled-coil domain which may take part in protein–protein interactions. Multiple alignment of DNAH11 protein sequence across multiple species shows that this region of the protein is well conserved and likely to be functionally important, so that the deletion would be deleterious to protein function. The ACMG classification was likely pathogenic. This was found in trans with a pathogenic stop gain variant in DNAH11, providing a confirmed diagnosis for this patient. b IGV screenshot showing heterozygous ~ 9.8 kb SV in HYDIN deleting exon 18 in case 13, affected sibling and mother but not father. This results in an in-frame deletion of amino acids 793–843 of the 5121 amino acid protein. Multiple alignment of HYDIN protein sequence across multiple species shows that this region of the protein is conserved and likely to be functionally important, but the ACMG classification was variant of uncertain significance because we couldn’t show that the deleted interval was critical to protein function. This was found in trans with a stop gain variant in HYDIN (also found in affected sibling and father), providing a probable diagnosis for this patient and their affected sibling. c Immunofluorescence confocal image of SPEF2 (red), ciliary axoneme marker alpha tubulin (green) and DAPI, overlaid with phase contrast image of single multiciliated cells from the nasal epithelium of health volunteer (left) and PCD case 13, who has a 9.8 k deletion in HYDIN in trans with a stop gain variant in HYDIN. HYDIN is required for trafficking of SPEF2 into the cilia, and so absence of SPEF2 in the cilia of this patient is supportive of the genetic findings in this patient