title: SPINK5 and ADRB2 haplotypes are risk factors for asthma in Mexican pediatric patients.
abstract: BACKGROUND
  Asthma is one of the most common respiratory diseases worldwide, and the complexity of its etiology has been widely documented. Chromosome 5q31-33 is one of the main loci implicated in asthma and asthma-related traits. IL13, CD14 and ADRB2, which are located in this risk locus, are among the genes most strongly associated with asthma susceptibility.
  
  
  OBJECTIVE
  This study evaluated whether single-nucleotide polymorphisms or haplotypes at 5q31-33 conferred risk for asthma in Mexican-Mestizo pediatric patients.
  
  
  METHODS
  We performed a case-controlled study including 851 individuals, 421 of them affected with childhood-onset asthma and 430 ethnically matched unaffected subjects. We used the TaqMan Allelic Discrimination Assay to genotype 20 single-nucleotide polymorphisms within IL5, RAD50, IL13, IL4, CD14, SPINK5, HTR4, ADRB2 and IL12B.
  
  
  RESULTS
  Although no association was detected for any risk allele, three SPINK5 haplotypes (GGCT: p = 6 × 10(-6); AATC: p = 0.0001; AGTT: p = 0.0001) and five ADRB2 haplotypes (AGGACC: p = 0.0014; AGGAAG: p = 0.0002; TGAGAG: p = 0.0001; AGGAAC: p = 0.0002; AAGGAG: p = 0.003) were associated with asthma. Notably, the AGTT SPINK5 haplotype exhibited a male gender-dependent association (p = 7.6 × 10(-5)).
  
  
  CONCLUSIONS
  Our results suggest that SPINK5 and ADRB2 haplotypes might play a role in the susceptibility to childhood-onset asthma.
authors.affiliation: Escuela Superior de Medicina, Instituto Politecnico Nacional , México City , Mexico .
authors.forename: N E
authors.initials: NE
authors.lastname: Martínez-Aguilar
authors.forename: B E
authors.initials: BE
authors.lastname: Del Río-Navarro
authors.forename: E
authors.initials: E
authors.lastname: Navarro-Olivos
authors.forename: H
authors.initials: H
authors.lastname: García-Ortíz
authors.forename: L
authors.initials: L
authors.lastname: Orozco
authors.forename: S
authors.initials: S
authors.lastname: Jiménez-Morales
mesh_terms: D000293:Adolescent; D000483:Alleles; D001249:Asthma / Q000208:ethnology / Q000235:genetics*; D002648:Child; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D007198:Indians, North American; D018793:Interleukin-13 / Q000235:genetics; D008297:Male; D008800:Mexico; D010328:Patch Tests; D020641:Polymorphism, Single Nucleotide; D053491:Proteinase Inhibitory Proteins, Secretory / Q000235:genetics*; D018343:Receptors, Adrenergic, beta-2 / Q000235:genetics*; D012307:Risk Factors; D000074163:Serine Peptidase Inhibitor Kazal-Type 5; D012720:Severity of Illness Index; D012737:Sex Factors
chemical_list: C553443:ADRB2 protein, human; D018793:Interleukin-13; D053491:Proteinase Inhibitory Proteins, Secretory; D018343:Receptors, Adrenergic, beta-2; C120650:SPINK5 protein, human; D000074163:Serine Peptidase Inhibitor Kazal-Type 5
keywords: 5q31-33 locus; ADRB2; SPINK5; asthma; case-controlled study; pediatric patients