title: Analysis of nitric oxide synthase genes in cluster headache.
abstract: The aetiology of cluster headache is still not yet completely understood, but the potential relevance of genetic factors has been recognized during recent years. Nitric oxide (NO) plays a critical role in the regulation of vasodilation, neurotransmission, inflammation and many other events throughout the body. NO also appears to be an important mediator of vascular headache pathophysiology. In this study we have performed an association analysis of five polymorphic microsatellite markers in the three different NO synthase (NOS) genes; nNOS (NOS1), iNOS (NOS2A) and eNOS (NOS3). Ninety-one cluster headache patients diagnosed according to International Headache Society criteria and 111 matched controls were studied. Phenotype and allele frequencies were similarly distributed in patients and controls except for an iNOS (NOS2A) pentanucleotide repeat allele which was significantly more common in controls. We observed a higher phenotype frequency of this allele in our control group compared with rates in control groups of other studies, whereas the frequency in our patients was similar to that in controls from previous reports. Thus, we conclude that it is unlikely that genetic variations within the NOS genes contribute greatly to cluster headache susceptibility.
authors.affiliation: Department of Neurology, Karolinska Institute, Huddinge University Hospital, Huddinge, Sweden. christina.sjostrand@neurotek.ki.se
authors.forename: C
authors.initials: C
authors.lastname: Sjöstrand
authors.forename: H
authors.initials: H
authors.lastname: Modin
authors.forename: T
authors.initials: T
authors.lastname: Masterman
authors.forename: K
authors.initials: K
authors.lastname: Ekbom
authors.forename: E
authors.initials: E
authors.lastname: Waldenlind
authors.forename: J
authors.initials: J
authors.lastname: Hillert
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D016009:Chi-Square Distribution; D003027:Cluster Headache / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D019001:Nitric Oxide Synthase / Q000032:analysis / Q000235:genetics*; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D010641:Phenotype
chemical_list: C496320:NOS1 protein, human; C496319:NOS2 protein, human; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III