Clinical and genetic characteristics of a case of primary ciliary dyskinesia caused by new frameshift mutation of the DNAH5 gene
Objective:To investigate the clinical and genetic characteristics of a case of primary ciliary dyskinesia(PCD).Methods:We collected the clinical data on a case of PCD treated in the Department of Reproductive Medicine of Linyi People's Hospi-tal in July 2020,detected the genes of the patient by whole-exome sequencing(WES),verified the candidate mutations by Sanger se-quencing,and predicted the protein structure of the mutant gene by SWISS-MODEL.Results:The proband was found with the clini-cal phenotypes of chronic rhinitis,bronchiectasis,visceral transposition and male infertility.WES revealed a homozygous frameshift variation of c.12890dup(p.N4297Kfs*13)in exon 74 of the DNAH5 gene,which led to the premature termination of polypeptide chain synthesis and affected the gene function.SWISS-MODEL prediction showed that some of the amino acid residues were deleted af-ter mutation,resulting in a 3D conformational change of the protein.This variation was not recorded in the ClinVar,gnomAD and OMIM databases and,according to the relevant guidelines of the American College of Genetics and Genomics,was classified as a path-ogenic variation(PVS1+PM2_P+PM3_P).Conclusion:The homozygous variation of the DNAH5 gene c.12890dup(p.N4297Kfs*13)may be the cause of the clinical phenotype of this case of PCD,and the above findings have enriched the variation spectrum of the DNAH5 gene.