title: Endothelin receptor A -231 G>A polymorphism: no linkage to primary pediatric headache.
abstract: OBJECTIVE
  To assess whether the biallelic -231 G>A polymorphism of the endothelin type A receptor (EDNRA) gene, previously shown to be a marker of increased risk for developing migraine, has a role in the susceptibility to primary pediatric headache.
  
  
  BACKGROUND
  Several studies suggest that endothelin has a role in migraine. A recent association study has shown that the biallelic -231 G>A polymorphism of the EDNRA gene is associated to migraine in an elderly population.
  
  
  METHODS
  A total of 126 consecutive unrelated pediatric patients affected by primary headache, classified according to the International Headache Society criteria in migraine (migraine with aura, n = 3; migraine without aura, n = 80), and tension-type headache (episodic tension-type headache, n = 36; chronic tension-type headache, n = 7) patients, were recruited to the study. Sixty-seven healthy blood donors were used as a control group. Genomic DNA was extracted from buccal swabs or blood samples and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for the above-mentioned polymorphism. Allele and genotype frequencies for primary headache patients were analyzed in comparison with the control group.
  
  
  RESULTS
  No significant differences were found in the distribution of the EDNRA -231 G>A polymorphic variant when considering both genotype (migraine chi2 = 2.78, P = .25; tension-type headache chi2 = 3.58, P = .17) and allelic frequencies (migraine chi2 = 1.48, P = .22; tension-type headache chi2 = 0.39, P = .56). Furthermore, no significant genotype-related difference was found in relation to clinical features, such as age at onset, frequency, and length of the attacks.
  
  
  CONCLUSIONS
  Our study shows that the -231 G>A polymorphism in the EDNRA gene is neither associated with primary juvenile headache nor significantly correlated with main clinical features characteristic of the headache pathology in pediatric settings.
authors.affiliation: Research and Innovation Company, Padova, Italy.
authors.forename: Veronica
authors.initials: V
authors.lastname: Lisi
authors.forename: Greta
authors.initials: G
authors.lastname: Garbo
authors.forename: PierAntonio
authors.initials: P
authors.lastname: Battistella
authors.forename: Flavia
authors.initials: F
authors.lastname: Miccichè
authors.forename: Anna
authors.initials: A
authors.lastname: Stecca
authors.forename: Salvatore
authors.initials: S
authors.lastname: Terrazzino
authors.forename: Malida
authors.initials: M
authors.lastname: Franzoi
authors.forename: Elisa
authors.initials: E
authors.lastname: Tripoli
authors.forename: Alberta
authors.initials: A
authors.lastname: Leon
authors.forename: Maurizio
authors.initials: M
authors.lastname: Clementi
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D020022:Genetic Predisposition to Disease; D006261:Headache / Q000235:genetics*; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic; D044022:Receptor, Endothelin A / Q000235:genetics*
chemical_list: D044022:Receptor, Endothelin A