Understanding Primary Ciliary Dyskinesia and Other Ciliopathies

Abstract

Ciliopathies are a collection of disorders related to cilia dysfunction. Cilia are specialized organelles that project from the surface of most cells. Motile and primary (sensory) cilia are essential structures and have wide ranging functions. Our understanding of the genetics, pathophysiology, and clinical manifestations of motile ciliopathies, including primary ciliary dyskinesia (PCD), has rapidly advanced since the disease was linked to ciliary ultrastructural defects nearly five decades ago. We will provide an overview of different types of cilia, their role in child health and disease, focusing on motile ciliopathies, and describe recent advances that have led to improved diagnostics and may yield therapeutic targets to restore ciliary structure and function.

Keywords: basal body; bronchiectasis; cilia; dynein; primary ciliary dyskinesia.

Figure 1.

Schematic diagram of a ciliary axoneme and basal body.

Figure 2.

Electron photomicrograph and diagram showing ultrastructural features of the motile cilium.

Figure 3.

Schematic diagrams depicting the general classification of motile and immotile cilia based on ultrastructural configuration and function.

Figure 4.

Classification of ultrastructural defects of the motile ciliary axoneme and genes associated with primary ciliary dyskinesia. IDA: inner dynein arm; ODA: outer dynein arm.