Abstract
Cilia are microtubule-based cellular organelles that are widely distributed in vertebrate tissues. They were first observed hundreds of years ago. Recent studies indicate that this small organelle plays important roles in numerous physiological phenomena, including tissue morphogenesis, signal transduction, determination of left-right asymmetry during development, and adult neurogenesis. Ciliopathies, syndromes resulting from a genetic disorder of cilial components, frequently have complex effects involving many organ systems, owing to the broad distribution of cilia in the body.