SSBP1 mutations in dominant optic atrophy with variable retinal degeneration

Jurkute, Neringa, Leu, Costin, Pogoda, Hans-Martin, Arno, Gavin, Robson, Anthony G., Nürnberg, Gudrun, Altmüller, Janine, Thiele, Holger, Motameny, Susanne, Toliat, Mohammad Reza, Powell, Kate, Höhne, Wolfgang, Michaelides, Michel, Webster, Andrew R., Moore, Anthony T., Hammerschmidt, Matthias, Nürnberg, Peter, Yu-Wai-Man, Patrick and Votruba, Marcela ORCID: https://orcid.org/0000-0002-7680-9135 2019. SSBP1 mutations in dominant optic atrophy with variable retinal degeneration. Annals of Neurology 86 (3) , pp. 368-383. 10.1002/ana.25550

Preview

PDF - Accepted Post-Print Version Download (1MB) | Preview

Abstract

Objective Autosomal dominant optic atrophy (ADOA) starts in early childhood with loss of visual acuity and color vision deficits. OPA1 mutations are responsible for the majority of cases, but in a proportion of patients with a clinical diagnosis of ADOA, the cause remains unknown. This study aimed to identify novel ADOA‐associated genes and explore their causality. Methods Linkage analysis and sequencing were performed in multi‐generation families and unrelated patients to identify disease‐causing variants. Functional consequences were investigated in silico and confirmed experimentally using the zebrafish model. Results We defined a new ADOA locus on 7q33‐q35 and identified three different missense variants in SSBP1 (NM_001256510.1; c.113G>A (p.(Arg38Gln)), c.320G>A (p.(Arg107Gln)) and c.422G>A (p.(Ser141Asn))) in affected individuals from two families and two singletons with ADOA and variable retinal degeneration. The mutated arginine residues are part of a basic patch that is essential for single‐strand DNA binding. The loss of a positive charge at these positions is very likely to lower the affinity of SSBP1 to ssDNA. Antisense‐mediated knockdown of endogenous ssbp1 mRNA in zebrafish resulted in compromised differentiation of retinal ganglion cells. A similar effect was achieved when mutated mRNAs were administered. These findings point to an essential role of ssbp1 in retinal development and the dominant‐negative nature of the identified human variants, which is consistent with the segregation pattern observed in two multi‐generation families studied. Interpretation SSBP1 is an essential protein for mtDNA replication and maintenance. Our data established pathogenic variants in SSBP1 as a cause of ADOA and variable retinal degeneration.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Optometry and Vision Sciences
Publisher:	Wiley
ISSN:	0364-5134
Funders:	MRC, Fight for Sight, Wellcome Trust
Date of First Compliant Deposit:	25 July 2019
Date of Acceptance:	10 July 2019
Last Modified:	13 Nov 2024 14:15
URI:	https://orca.cardiff.ac.uk/id/eprint/124475

Citation Data

Cited 43 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item