Primary ciliary dyskinesia (PCD) is a rare genetic disorder leading to recurrent 
respiratory tract infections. High-speed video-microscopy analysis (HVMA) of 
ciliary beating, currently the first-line diagnostic tool for PCD in most 
centres, is challenging because recent studies have expanded the spectrum of 
HVMA findings in PCD from grossly abnormal to very subtle. The objective of this 
study was to describe the diversity of HVMA findings in genetically confirmed 
PCD individuals. HVMA was performed as part of the routine work-up of 
individuals with suspected PCD. Subsequent molecular analysis identified 
biallelic mutations in the PCD-related genes of 66 individuals. 1072 videos of 
these subjects were assessed for correlation with the genotype. Biallelic 
mutations (19 novel) were found in 17 genes: DNAI1, DNAI2, DNAH5, DNAH11, 
CCDC103, ARMC4, KTU/DNAAF2, LRRC50/DNAAF1, LRRC6, DYX1C1, ZMYND10, CCDC39, 
CCDC40, CCDC164, HYDIN, RSPH4A and RSPH1. Ciliary beat pattern variations 
correlated well with the genetic findings, allowing the classification of 
typical HVMA findings for different genetic groups. In contrast, analysis of 
ciliary beat frequency did not result in additional diagnostic impact. In 
conclusion, this study provides detailed knowledge about the diversity of HVMA 
findings in PCD and may therefore be seen as a guide to the improvement of PCD 
diagnostics.