title: [Association between tryptophan hydroxylase gene polymorphisms and attention deficit hyperactivity disorder with or without learning disorder].
abstract: OBJECTIVE
  To investigate the relationship between two tryptophan hydroxylasec (TPH) gene polymorphisms, A218C and A-6526G polymorphisms, and attention deficit hyperactivity disorder (ADHD) with or without learning disorder (LD).
  
  
  METHODS
  Blood samples were taken from 132 trios with probands of ADHD with LD and 221 trios with probands of ADHD without LD. DNA was extracted and PCR was performed to amplify the fragments of A218C amd A-6526G polymorphisms. NheI and MboI were used to detect different alleles of the two polymorphisms separately. transmission disequilibriumtest (TDT) and haplotype analysis were used to test the association of the two polymorphisms of TPH gene and ADHD with or without LD.
  
  
  RESULTS
  Haplotype block composed by A218C and A-6526G polymorphisms was related to ADHD with LD (chi(2) = 9.362, df = 3, P = 0.025). The haplotype of 218A/-6526G was significantly untransmitted to the probands with ADHD with LD (chi(2) = 9.252, df = 1, P = 0.002).
  
  
  CONCLUSIONS
  TPH gene and the haplotype of 218A/-6526G may be related to ADHD with LD.
authors.affiliation: Peking University Institute of Mental Health, Beijing 10083, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Yu-feng
authors.initials: YF
authors.lastname: Wang
authors.forename: Ru-lun
authors.initials: RL
authors.lastname: Zhou
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Hao-bo
authors.initials: HB
authors.lastname: Zhang
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000201:enzymology / Q000235:genetics*; D002648:Child; D005260:Female; D006239:Haplotypes; D006801:Humans; D007859:Learning Disabilities / Q000201:enzymology / Q000235:genetics*; D008297:Male; D011110:Polymorphism, Genetic; D014365:Tryptophan Hydroxylase / Q000235:genetics*
chemical_list: D014365:Tryptophan Hydroxylase