PUBLICATION

Mutations in ARMC9, which Encodes a Basal Body Protein, Cause Joubert Syndrome in Humans and Ciliopathy Phenotypes in Zebrafish

Authors

Van De Weghe, J.C., Rusterholz, T.D.S., Latour, B., Grout, M.E., Aldinger, K.A., Shaheen, R., Dempsey, J.C., Maddirevula, S., Cheng, Y.H., Phelps, I.G., Gesemann, M., Goel, H., Birk, O.S., Alanzi, T., Rawashdeh, R., Khan, A.O., Bamshad, M.J., Nickerson, D.A., Neuhauss, S.C.F., Dobyns, W.B., Alkuraya, F.S., Roepman, R., Bachmann-Gagescu, R., Doherty, D.

ID

ZDB-PUB-170621-14

Date

2017

Source

American journal of human genetics 101(1): 23-36 (Journal)

Registered Authors

Bachmann-Gagescu, Ruxandra, Gesemann, Matthias, Neuhauss, Stephan, Phelps, Ian

Keywords

ARMC9, Joubert syndrome, basal body, cilia, ciliopathy, primary cilium, zebrafish

MeSH Terms

Abnormalities, Multiple/genetics*
Abnormalities, Multiple/pathology
Animals
Armadillo Domain Proteins/genetics*
Armadillo Domain Proteins/metabolism
Basal Bodies/metabolism*
Base Sequence
Brain/pathology
Cerebellum/abnormalities*
Cerebellum/pathology
Cilia/metabolism
Ciliopathies/genetics*
Ciliopathies/pathology
Diagnostic Imaging
Exome/genetics
Eye Abnormalities/genetics*
Eye Abnormalities/pathology
Genetic Predisposition to Disease
Humans
Kidney Diseases, Cystic/genetics*
Kidney Diseases, Cystic/pathology
Mutation/genetics*
Phenotype
Retina/abnormalities*
Retina/pathology
Sequence Analysis, DNA
Up-Regulation/genetics
Zebrafish/genetics*
Zebrafish Proteins/genetics*
Zebrafish Proteins/metabolism

PubMed

28625504 Full text @ Am. J. Hum. Genet.

Abstract

Joubert syndrome (JS) is a recessive neurodevelopmental disorder characterized by hypotonia, ataxia, abnormal eye movements, and variable cognitive impairment. It is defined by a distinctive brain malformation known as the "molar tooth sign" on axial MRI. Subsets of affected individuals have malformations such as coloboma, polydactyly, and encephalocele, as well as progressive retinal dystrophy, fibrocystic kidney disease, and liver fibrosis. More than 35 genes have been associated with JS, but in a subset of families the genetic cause remains unknown. All of the gene products localize in and around the primary cilium, making JS a canonical ciliopathy. Ciliopathies are unified by their overlapping clinical features and underlying mechanisms involving ciliary dysfunction. In this work, we identify biallelic rare, predicted-deleterious ARMC9 variants (stop-gain, missense, splice-site, and single-exon deletion) in 11 individuals with JS from 8 families, accounting for approximately 1% of the disorder. The associated phenotypes range from isolated neurological involvement to JS with retinal dystrophy, additional brain abnormalities (e.g., heterotopia, Dandy-Walker malformation), pituitary insufficiency, and/or synpolydactyly. We show that ARMC9 localizes to the basal body of the cilium and is upregulated during ciliogenesis. Typical ciliopathy phenotypes (curved body shape, retinal dystrophy, coloboma, and decreased cilia) in a CRISPR/Cas9-engineered zebrafish mutant model provide additional support for ARMC9 as a ciliopathy-associated gene. Identifying ARMC9 mutations as a cause of JS takes us one step closer to a full genetic understanding of this important disorder and enables future functional work to define the central biological mechanisms underlying JS and other ciliopathies.

Genes / Markers

Figures

Show all Figures

Expression

Phenotype

Mutations / Transgenics

Human Disease / Model

Sequence Targeting Reagents

Fish

Antibodies

Orthology

Engineered Foreign Genes

Mapping

Van De Weghe et al., 2017 ZDB-PUB-170621-14 PMID:28625504

Mutations in ARMC9, which Encodes a Basal Body Protein, Cause Joubert Syndrome in Humans and Ciliopathy Phenotypes in Zebrafish

Van De Weghe et al., 2017

ZDB-PUB-170621-14
PMID:28625504