title: Association between two polymorphisms of histamine-metabolising enzymes and the severity of allergic rhinitis in a group of Mexican children.
abstract: BACKGROUND
  It has been suggested that polymorphisms of histamine metabolising enzymes can be a risk factor for developing histamine-involving diseases. The aim of the present study is to research the possible association between two functional single nucleotide polymorphisms (SNPs): C314T in the Histamine-N-Methyl Transferase gene and C2029G in the Diamine Oxidase gene, with the severity of allergic rhinitis and the number of allergic diseases, in a group of allergic Mexican children.
  
  
  METHODS
  We studied 154 unrelated allergic children. SNPs were analysed by RT-PCR. The total serum IgE was measured by chemiluminescence and the serum histamine by ELISA. We used logistic regression analysis to determine OR.
  
  
  RESULTS
  Patients carrying the mutant allele for any SNP had more risk to develop higher rhinitis severity or a bigger number of allergic diseases. Haplotype analysis revealed that this effect is synergistic. In patients carrying one or two mutant alleles, serum histamine levels were higher than those of patients carrying only wild alleles. Serum IgE levels were not associated with the presence of mutant alleles.
  
  
  CONCLUSIONS
  The presence of these SNPs in patients with allergic rhinitis can lead to higher serum histamine, therefore to a higher risk of developing more severe symptoms or more associated allergic diseases, even if the serum IgE remains low.
authors.affiliation: Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico; Facultad de Medicina, Universidad Autonóma de Coahuila, Mexico.
authors.forename: R
authors.initials: R
authors.lastname: Meza-Velázquez
authors.affiliation: Facultad de Medicina, Universidad Autonóma de Coahuila, Mexico.
authors.forename: F
authors.initials: F
authors.lastname: López-Márquez
authors.affiliation: Instituto Nacional de Pediatría, Mexico.
authors.forename: S
authors.initials: S
authors.lastname: Espinosa-Padilla
authors.affiliation: Facultad de Medicina, Universidad Autonóma de Coahuila, Mexico; Secretaría de Salud, Torreón, Coahuila, Mexico.
authors.forename: M
authors.initials: M
authors.lastname: Rivera-Guillen
authors.affiliation: Secretaría de Educación Pública. Durango, Mexico.
authors.forename: N
authors.initials: N
authors.lastname: Gutíerrez-Díaz
authors.affiliation: Secretaría de Salud, Torreón, Coahuila, Mexico.
authors.forename: L
authors.initials: L
authors.lastname: Pérez-Armendáriz
authors.affiliation: Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico. Electronic address: manuel_rosales_9@hotmail.com.
authors.forename: M
authors.initials: M
authors.lastname: Rosales-González
mesh_terms: D006631:Amine Oxidase (Copper-Containing) / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D018450:Disease Progression; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006632:Histamine / Q000097:blood; D006637:Histamine N-Methyltransferase / Q000235:genetics*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008800:Mexico; D020641:Polymorphism, Single Nucleotide; D065631:Rhinitis, Allergic / Q000235:genetics*
chemical_list: D007073:Immunoglobulin E; D006632:Histamine; D006631:Amine Oxidase (Copper-Containing); D006637:Histamine N-Methyltransferase
keywords: Allergic rhinitis; Diamine oxidase; Histamine; Histamine-N-methyl transferase; Polymorphisms