Fifteen years of research on oral-facial-digital syndromes: from 1 to 16 causal genes.

Abstract

Oral-facial-digital syndromes (OFDS) gather rare genetic disorders characterised by facial, oral and digital abnormalities associated with a wide range of additional features (polycystic kidney disease, cerebral malformations and several others) to delineate a growing list of OFDS subtypes. The most frequent, OFD type I, is caused by a heterozygous mutation in the OFD1 gene encoding a centrosomal protein. The wide clinical heterogeneity of OFDS suggests the involvement of other ciliary genes. For 15 years, we have aimed to identify the molecular bases of OFDS. This effort has been greatly helped by the recent development of whole-exome sequencing (WES). Here, we present all our published and unpublished results for WES in 24 cases with OFDS. We identified causal variants in five new genes (C2CD3, TMEM107, INTU, KIAA0753 and IFT57) and related the clinical spectrum of four genes in other ciliopathies (C5orf42, TMEM138, TMEM231 and WDPCP) to OFDS. Mutations were also detected in two genes previously implicated in OFDS. Functional studies revealed the involvement of centriole elongation, transition zone and intraflagellar transport defects in OFDS, thus characterising three ciliary protein modules: the complex KIAA0753-FOPNL-OFD1, a regulator of centriole elongation; the Meckel-Gruber syndrome module, a major component of the transition zone; and the CPLANE complex necessary for IFT-A assembly. OFDS now appear to be a distinct subgroup of ciliopathies with wide heterogeneity, which makes the initial classification obsolete. A clinical classification restricted to the three frequent/well-delineated subtypes could be proposed, and for patients who do not fit one of these three main subtypes, a further classification could be based on the genotype.

• Authors: Ange-Line Bruel, Brunella Franco, Yannis Duffourd, Julien Thevenon, Laurence Jego, Estelle Lopez, Jean-François Deleuze, Diane Doummar, Rachel H Giles, Colin A Johnson, Martijn A Huynen, Véronique Chevrier, Lydie Burglen, Manuela Morleo, Isabelle Desguerres, Geneviève Pierquin, Bérénice Doray, Brigitte Gilbert-Dussardier, Bruno Reversade, Elisabeth Steichen-Gersdorf, Clarisse Baumann, Inusha Panigrahi, Anne Fargeot-Espaliat, Anne Dieux, Albert David, Alice Goldenberg, Ernie Bongers, Dominique Gaillard, Jesús Argente, Bernard Aral, Nadège Gigot, Judith St-Onge, Daniel Birnbaum, Shubha R Phadke, Valérie Cormier-Daire, Thibaut Eguether, Gregory J Pazour, Vicente Herranz-Pérez, Jaclyn S Goldstein, Laurent Pasquier, Philippe Loget, Sophie Saunier, André Mégarbané, Olivier Rosnet, Michel R Leroux, John B Wallingford, Oliver E Blacque, Maxence V Nachury, Tania Attie-Bitach, Jean-Baptiste Rivière, Laurence Faivre, Christel Thauvin-Robinet
• Journal: Journal of medical genetics (J Med Genet) Vol. 54 Issue 6 Pg. 371-380 (06 2017) ISSN: 1468-6244 [Electronic] England
• PMID: 28289185 (Publication Type: Journal Article, Review)
• Copyright: © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Chemical References

• Proteins

Topics

• Abnormalities, Multiple (genetics)
• Ciliary Motility Disorders (genetics)
• Encephalocele (genetics)
• Face (abnormalities)
• Female
• Heterozygote
• Humans
• Male
• Mutation (genetics)
• Orofaciodigital Syndromes (genetics)
• Polycystic Kidney Diseases (genetics)
• Proteins (genetics)
• Retinitis Pigmentosa