title: Y2 receptor gene variants reduce the risk of hypertension in obese children and adolescents.
abstract: OBJECTIVE
  To verify whether peptide YY (PYY) and its Y2 receptor (Y2R) gene variants can be associated with obesity or hypertension or both in a cohort of obese children and adolescents.
  
  
  METHODS
  Two hundred and twenty-nine obese children (105 girls, mean z-score BMI 5.1 +/- 2.4; mean age 10.5 +/- 2.9 years) and 250 age and sex-matched lean controls (130 women, mean z-score BMI 0.5 +/- 1.1; mean age 10.3 +/- 2.8) were enrolled in the study. Height, weight, BMI, waist circumference and 24-h systolic and diastolic blood pressure were measured. Night-time, day-time and 24-h systolic and diastolic blood pressures were evaluated by 24 h ambulatory blood pressure measurement, and appropriate standard deviation scores according to sex, age and height were calculated. Molecular screening of the PYY and Y2R genes was performed.
  
  
  RESULTS
  No new mutations were found. We observed three previously described polymorphisms: G767C on PYY and T585C and T936C on Y2R. An association study was carried out in obese patients. No associations were found between the PYY genotypes and the studied phenotypes. The Y2R gene variants, T585C and T936C, which are in almost complete linkage disequilibrium, were found to be associated with night-time, day-time and 24-h systolic and diastolic blood pressures. In particular, subject homozygotes for the T allele showed lower systolic and diastolic blood pressure values compared with the other genotypes. Moreover, obese children homozygous for the T585 allele showed a lower risk of developing hypertension than patients carrying the CC and CT genotypes (chi 6.9; df = 1, P = 0.03; odds ratio = 0.5, 95% confidence interval: 0.27-0.88).
  
  
  CONCLUSIONS
  Our results suggest that Y2R gene variants are involved in blood pressure regulation in obese children and adolescents.
authors.affiliation: Department of Pediatrics, Monaldi Hospital, Second University of Naples, Naples, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Santoro
authors.forename: Emanuele Miraglia
authors.initials: EM
authors.lastname: Del Giudice
authors.forename: Anna
authors.initials: A
authors.lastname: Grandone
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Marzuillo
authors.forename: Domenico
authors.initials: D
authors.lastname: Cozzolino
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Salvo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pacileo
authors.forename: Raffaele
authors.initials: R
authors.lastname: Calabrò
authors.forename: Laura
authors.initials: L
authors.lastname: Perrone
mesh_terms: D000293:Adolescent; D001794:Blood Pressure / Q000235:genetics; D018660:Blood Pressure Monitoring, Ambulatory; D002648:Child; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006720:Homozygote; D006801:Humans; D006973:Hypertension / Q000453:epidemiology* / Q000235:genetics*; D016014:Linear Models; D008297:Male; D009765:Obesity / Q000453:epidemiology* / Q000235:genetics*; D010641:Phenotype; D011110:Polymorphism, Genetic; D017476:Receptors, Neuropeptide Y / Q000235:genetics*; D012307:Risk Factors
chemical_list: D017476:Receptors, Neuropeptide Y; C095889:neuropeptide Y2 receptor