Cluster headache (CH) is characterized by severe, recurrent, unilateral attacks of extreme intensity and brief duration. Variants in a myriad of genes were studied in sporadic CH patients, often with conflicting results.
We studied gene mutations in some candidate genes, hypocretin receptor 2, Clock, and alcohol dehydrogenase 4 (ADH4), in 54 unrelated sporadic CH patients and in 200 controls in 8 kindreds/families that included more affected and nonaffected cases. Furthermore, we performed the whole-genome scanning by comparative genomic hybridization, searching for rearrangements associated with DNA gain or loss in a subset of sporadic and familial CH and control participants.
The analysis of candidate genes revealed that only allele and genotype frequency of the 2 ADH4 mutations resulted significantly between sporadic CH and controls; the same mutations were homozygous in CH patients from 2 families. The comparative genomic hybridization analysis revealed 2 novel rearrangements that involved the intron regions of thyrotropin-releasing hormone-degrading enzyme and neurexin 3 (NRXN3) genes, respectively. The first arrangement was present either in CH or in controls, whereas the second one was specifically found in some sporadic and familial CH cases.
Our data (although obtained on a small number of cases) confirm the genetic heterogeneity of CH, suggesting that mutations in the ADH4 gene and a novel rearrangement involving NRXN3 gene might be related to CH in a subset of cases.
*Dipartimento di Bioscienze e Territorio, Università del Molise, Isernia, Italy
†Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Naples, Italy
§Dipartimento di Medicina Clinica e Chirurgia, Università di Napoli Federico II, Naples, Italy
∥Dipartimento di Neuroscienze e Scienze Riproduttive e Odontostomatologiche, Università di Napoli Federico II, Naples, Italy
‡CEINGE-Biotecnologie Avanzate, Naples, Italy
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Supported by a grant from Regione Campania (DGRC 1901/2009) and by POR Campania FSE 2007-13, Project CREME. It was a contribution of Campania region (public administration) aimed to fund research and diagnostics in the field of genes related to human disorders. The authors declare no conflict of interest.
Reprints: Giuseppe Castaldo, MD, PhD, CEINGE-Biotecnologie Avanzate, Via Gaetano Salvatore 486, I-80145, Naples, Italy (e-mail: firstname.lastname@example.org).
Received November 15, 2013
Received in revised form February 13, 2014
Accepted January 15, 2014