Overview of primary ciliary dyskinesia causing genes and their associated findings by transmission electron microscopy (TEM) and immunofluorescence analyses
| Gene | [Ref.] | Locus | TEM | Immunofluorescence |
| DNAH5 | [65] | 5p15 | ODA | Absent DNAH5 and DNAH9 [67, 94, 95] |
| DNAH11 | [49] | 7p15–21 | Normal | DNAH11 is absent in patients with DNAH11 loss-of function mutations, DNAH5 and DNALI1 present [96, 97] |
| DNAI1 | [66] | 9p21-p13 | ODA | DNAH5 staining may be present proximally but absent distally, DNAH9 absent within the ciliary axonemes [67, 94] |
| DNAI2 | [67] | 17q25.1 | ODA | DNAH5, DNAI2 and DNAH9 absent or aberrant [67] |
| NME8 (TXNDC3) | [68] | 7p14.1 | ODA | Not reported |
| DNAL1 | [69] | 14q24.3 | ODA | Not reported |
| CCDC151 | [70] | 19p13.2 | ODA | DNAH5, CDC151, CCDC114 and ARMC4 absent, DNALI1 present [70] |
| CCDC114 | [71] | 19q13.33 | ODA | CCDC114 severely reduced, DNAH5 absent, DNALI1 undisturbed [71] |
| ARMC4 | [72] | 10p21 | ODA | Reduced ARMC4 staining along cilia, complete distal loss of DNAH5, DNAH5 only on proximal ciliary end, DNALI1 present [72, 98] |
| CCDC103 | [73] | 17q12 | ODA+IDA | DNAH5, DNAH9 and DNALI1 are missing or reduced in a small number of patients [73] |
| DYX1C1 (DNAAF4) | [74] | 15q21 | ODA+IDA | DNAH5, DNAH9 and DNAI2 absent [74] |
| SPAG1 | [75] | 8q22 | ODA+IDA | Absent DNAH5 and DNALI1 [75] |
| LRRC6 | [76] | 8q24 | ODA+IDA | LRRC6, DNALI1 and DNAI2 absent or very reduced [76, 82, 99] |
| DNAAF2 (KTU) | [77] | 14q21.3 | ODA+IDA | DNAH5 and DNAI2 absent distally with some residual staining, DNAH9 and DNALI1 absent [77] |
| DNAAF1 (LRRC50) | [78, 79] | 16q24 | ODA+IDA | DNAH5, DNAH9 and DNALI1 absent [79] |
| C21orf59 | [80] | 21q22.1 | ODA+IDA | DNAH5 and DNALI1 absent [80] |
| DNAAF3 | [81] | 19q13 | ODA+IDA | DNAH5, DNAH9 and DNALI1 absent [81] |
| ZMYND10 | [82] | 3p21.3 | ODA+IDA | DNAH5, DNAI2 and DNALI1 absent [82, 100] |
| DNAAF5 (HEATR2) | [83] | 7p22.3 | ODA+IDA | DNAI1, DNAH5 and DNALI1 absent, HEATR2 reduced [83, 101] |
| HYDIN | [84] | 16q22 | Normal/subtle: increased frequency of transposition defects | Normal IDA (DNALI1) and ODA (DNAH5) [84] |
| RSPH1 | [32] | 21q22.3 | Intermittent central pair/transposition defects | RSPH1 and RSPH9 absent, RSPH4A present [32, 86, 102] |
| RSPH3 | [85] | 6q25.3 | Intermittent central pair/near absence of radial spokes | RSPH3 and RSPH11 absent, RSPH1, RSPH4A and RSPH23 present (RSPH9 not reported), DNALI1 present [85] |
| RSPH9 | [86] | 6p21 | Intermittent central pair defect/transposition | Absent RSPH9, RSPH1 and RSPH4A present [86] |
| RSPH4A | [86] | 6q22 | Intermittent central pair defect/transposition | RSPH4A, RSPH9 and RSPH1 absent [86] |
| DRC1 (CCDC164) | [87] | 2p23 | Normal/subtle: N-DRC links missing with occasional MT disorganisation | GAS8 and LRRC48 absent from ciliary axonemes [87] |
| GAS8 (DRC4) | [30] | 16q24.3 | Normal/subtly abnormal: increased frequency of MT misalignment | DNALI1 and DNAH5 present, GAS8 absent [30] |
| CCDC65 (DRC2) | [88] | 12q13.12 | Normal/N-DRC links missing with occasional MT disorganisation | CCDC65 and GAS8 reduced [88] |
| CCDC39 | [89] | 3q26 | MT disorganisation+IDA | Absent CCDC39 protein, ODA normal distribution (DNAH5, DNAI2, DNAH9), DNALI1 (IDA) absent, GAS8 in cytoplasm but absent from axoneme [89, 103] |
| CCDC40 | [90] | 17q25 | MT disorganisation+IDA | Absent CCDC39 protein, RSPH4A and ROPN1 L/RSP11 present in axonemes [90, 103] |
| RPGR# | [91] | Xp21.1 | Variable | Normal, DNAH5 and DNALI1 present [104] |
| OFD1¶ | [92] | Xp22 | Unknown | Not reported |
| CCNO | [64] | 5q11.2 | Reduction of cilia number | DNAH5 present, rootletin mislocated in deeper regions of cytoplasm, CCNO not detectable [64] |
| MCIDAS | [93] | 5q11.2 | Reduction of cilia number | MCIDAS, CCNO, DNAH5, CCDC39 and CCDC78 absent [93] |
ODA: outer dynein arm; IDA: inner dynein arm; N-DRC: nexin link-dynein regulatory complex; MT: microtubular. #: retinitis pigmentosa usually detected in adult patients; ¶: rare syndromic phenotype.