Shared loci for migraine and epilepsy on chromosomes 14q12-q23 and 12q24.2-q24.3

Abstract

Objectives:To describe clinical characteristics and to identify susceptibility loci for epilepsy and migraine in a Finnish family with a complex phenotype. Methods:Participating family members were interviewed and medical files were reviewed. The seizure classification was made according to International League Against Epilepsy criteria. Migraine diagnosis was made using the validated Finnish Migraine Specific Questionnaire for Family Studies and criteria according to the current International Classification of Headache Disorders-II. DNA samples were obtained from 56 family members and nonparametric genome-wide linkage analyses were performed using 382 polymorphic microsatellite markers. The most promising loci were fine-mapped with additional microsatellite markers.Results: Clinical data were obtained from 60 family members of whom 12 (20%) had idiopathic epileptic seizures. Eight of those 12 (67%) also had migraine. Altogether 33 of the 60 family members (55%) had migraine. Significant evidence of linkage was found between a locus on 14q12-q23 and migraine (p ϭ 0.0001). Suggestive evidence of linkage in this region was also found for epilepsy with generalized tonic-clonic seizures (p ϭ 0.0034). In addition, significant evidence of linkage was found at a locus on 12q24.2-q24.3 (p Ͻ 0.001) for migraine alone and for the combined phenotype of migraine and epilepsy. Conclusions:Our data suggest the occurrence of common susceptibility loci for epilepsy and migraine on chromosomes 14q12-q23 and 12q24.2-q24.3, implicating a shared genetic etiology for these 2 diseases. Neurology ® 2012;78:202-209 GLOSSARY ASP ϭ affected sib-pairs; E ϭ epilepsy; FS ϭ febrile seizures; GTCS ϭ generalized tonic-clonic seizures; GWS ϭ genomewide scan; M ϭ migraine with or without aura; MA ϭ migraine with aura; M؉E ϭ combined migraine or epilepsy; MO ϭ migraine without aura; NCBI ϭ National Center for Biotechnology Information; NPL ϭ nonparametric linkage; SNP ϭ single nucleotide polymorphism; SUA ϭ somnolence unconsciousness attacks.Epilepsy and migraine are chronic paroxysmal neurologic disorders 1 that show high comorbidity. The prevalence of epilepsy in Europe is estimated to be 0.3-0.8% 2 and of migraine 11-15%.3-5 Of patients with migraine, 6% have epilepsy and up to 26% of patients with epilepsy have migraine. 6 -9

Migraine in the borderland of epilepsy: “Migralepsy” an overlapping syndrome of children and adults?

“…Another five‐generational family with febrile seizures, epilepsy (generalized tonic–clonic seizures), migraine either with (22%) or without aura (33%), and a PPR in some patients, showed linkage to chromosomes 14q and 12q (Polvi et al., 2012). Both loci are linked to epilepsy and migraine.…”

Cross section comparative study for comorbid migraine and major depression in epileptic patients: demographic, clinical, electroencahpalograhy and therapeutic implications

“…In addition, significant evidence of linkage was found at a locus on 12q24.2-q24.3 for migraine alone and for the combined phenotype of migraine and epilepsy. These data suggest the occurrence of common susceptibility loci for epilepsy and migraine on chromosomes 14q12-q23 and 12q24.2-q24.3, implicating a shared genetic etiology for these two disorders (Polvi et al, 2012).…”

“…The idea that migraine may lead to epilepsy was once proposed as an explanation for the comorbidity (Le et al, 2011;Polvi et al, 2012). Epidemiological data indicate that this explanation is unlikely (Silberstein et al, 2008).…”

Shared Loci for Migraine and Epilepsy on Chromosomes 14q12-q23 and 12q24.2-q24.3

“…Millichap and Nordli for their interest in our article. 1 We investigated and discussed the clinical features and classification of the SUA attacks. Three reasons led us to use the term SUA.…”

“…The possibility of a spectrum of benign childhood focal epilepsies including rolandic epilepsy, PS, and idiopathic and photosensitive childhood occipital epilepsy of Gastaut 5 should be considered particularly when prospectively examining the newer generation of this family. 1 We adopted a conservative view on the SUA events due to lack of EEG data and the narrow spectrum of autonomic features during the events reported in our patients. PS, as a recently acknowledged entity, is most likely underdiagnosed 6 and this might have happened in our study.…”