A case of primary ciliary dyskinesis with DRC1 deletion and literature review: Additional evidence on the founder effect

Abstract

BackgroundPrimary ciliary dyskinesia (PCD) is a rare genetic disease caused by defects in various genes affecting ciliary function. It is currently unclear why DRC1 gene variants are a relatively frequent cause of disease in Japanese and Korean patients.MethodsA 12‐year‐old Japanese girl with bronchiectasis was suspected of PCD and examined using whole‐exome sequencing (WES). The breakpoint region was confirmed by Sanger sequencing and evaluation of transposable elements.ResultsWhole‐exome sequencing revealed a deletion of DRC1 exons 1–4 in the patient, followed by validation with Sanger sequencing. A DRC1 exon 1–4 deletion is recurrently observed in Japanese and Korean patients with PCD. All reported patients carry the same breakpoint region, which shows signs of Alu‐mediated recombination. Intriguingly, common haplotypes were observed around the DRC1 gene in Japanese and Korean patients.ConclusionThe recurrent DRC1 exon 1–4 deletion is therefore likely to be a founder variant and should be considered a major genetic cause of PCD in Japanese and Korean patients with PCD.