RT Journal Article
SR Electronic
T1 Heterogeneous contribution of microdeletions in the development of common generalised and focal epilepsies
JF Journal of Medical Genetics
JO J Med Genet
FD BMJ Publishing Group Ltd
SP 598
OP 606
DO 10.1136/jmedgenet-2016-104495
VO 54
IS 9
A1 Pérez-Palma, Eduardo
A1 Helbig, Ingo
A1 Klein, Karl Martin
A1 Anttila, Verneri
A1 Horn, Heiko
A1 Reinthaler, Eva Maria
A1 Gormley, Padhraig
A1 Ganna, Andrea
A1 Byrnes, Andrea
A1 Pernhorst, Katharina
A1 Toliat, Mohammad R
A1 Saarentaus, Elmo
A1 Howrigan, Daniel P
A1 Hoffman, Per
A1 Miquel, Juan Francisco
A1 De Ferrari, Giancarlo V
A1 Nürnberg, Peter
A1 Lerche, Holger
A1 Zimprich, Fritz
A1 Neubauer, Bern A
A1 Becker, Albert J
A1 Rosenow, Felix
A1 Perucca, Emilio
A1 Zara, Federico
A1 Weber, Yvonne G
A1 Lal, Dennis
YR 2017
UL http://jmg.bmj.com/content/54/9/598.abstract
AB Background Microdeletions are known to confer risk to epilepsy, particularly at genomic rearrangement ‘hotspot’ loci. However, microdeletion burden not overlapping these regions or within different epilepsy subtypes has not been ascertained.Objective To decipher the role of microdeletions outside hotspots loci and risk assessment by epilepsy subtype.Methods We assessed the burden, frequency and genomic content of rare, large microdeletions found in a previously published cohort of 1366 patients with genetic generalised epilepsy (GGE) in addition to two sets of additional unpublished genome-wide microdeletions found in 281 patients with rolandic epilepsy (RE) and 807 patients with adult focal epilepsy (AFE), totalling 2454 cases. Microdeletions were assessed in a combined and subtype-specific approaches against 6746 controls.Results When hotspots are considered, we detected an enrichment of microdeletions in the combined epilepsy analysis (adjusted p=1.06×10−6,OR 1.89, 95% CI 1.51 to 2.35). Epilepsy subtype-specific analyses showed that hotspot microdeletions in the GGE subgroup contribute most of the overall signal (adjusted p=9.79×10−12, OR 7.45, 95% CI 4.20–13.5). Outside hotspots , microdeletions were enriched in the GGE cohort for neurodevelopmental genes (adjusted p=9.13×10−3,OR 2.85, 95% CI 1.62–4.94). No additional signal was observed for RE and AFE. Still, gene-content analysis identified known (NRXN1, RBFOX1 and PCDH7) and novel (LOC102723362) candidate genes across epilepsy subtypes that were not deleted in controls.Conclusions Our results show a heterogeneous effect of recurrent and non-recurrent microdeletions as part of the genetic architecture of GGE and a minor contribution in the aetiology of RE and AFE.