Primary Cilia Defects Causing Mitral Valve Prolapse

Sci Transl Med. 2019 May 22;11(493):eaax0290. doi: 10.1126/scitranslmed.aax0290.

Abstract

Mitral valve prolapse (MVP) affects 1 in 40 people and is the most common indication for mitral valve surgery. MVP can cause arrhythmias, heart failure, and sudden cardiac death, and to date, the causes of this disease are poorly understood. We now demonstrate that defects in primary cilia genes and their regulated pathways can cause MVP in familial and sporadic nonsyndromic MVP cases. Our expression studies and genetic ablation experiments confirmed a role for primary cilia in regulating ECM deposition during cardiac development. Loss of primary cilia during development resulted in progressive myxomatous degeneration and profound mitral valve pathology in the adult setting. Analysis of a large family with inherited, autosomal dominant nonsyndromic MVP identified a deleterious missense mutation in a cilia gene, DZIP1 A mouse model harboring this variant confirmed the pathogenicity of this mutation and revealed impaired ciliogenesis during development, which progressed to adult myxomatous valve disease and functional MVP. Relevance of primary cilia in common forms of MVP was tested using pathway enrichment in a large population of patients with MVP and controls from previously generated genome-wide association studies (GWAS), which confirmed the involvement of primary cilia genes in MVP. Together, our studies establish a developmental basis for MVP through altered cilia-dependent regulation of ECM and suggest that defects in primary cilia genes can be causative to disease phenotype in some patients with MVP.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism
  • Animals
  • Base Sequence
  • Cilia / pathology*
  • Extracellular Matrix / metabolism
  • Female
  • Genome-Wide Association Study
  • Heart Valves / diagnostic imaging
  • Heart Valves / growth & development
  • Humans
  • Male
  • Mice, Knockout
  • Mitral Valve Prolapse / diagnostic imaging
  • Mitral Valve Prolapse / etiology*
  • Mitral Valve Prolapse / genetics
  • Morphogenesis
  • Pedigree
  • Time Factors
  • Tumor Suppressor Proteins / metabolism

Substances

  • Adaptor Proteins, Signal Transducing
  • DZIP1 protein, human
  • Dzip1 protein, mouse
  • Tg737Rpw protein, mouse
  • Tumor Suppressor Proteins