title: Family based association analysis of statistically derived quantitative traits for drug use in ADHD and the dopamine transporter gene.
abstract: OBJECTIVE
  To determine whether SNPs within the dopamine transporter gene (DAT) are associated with quantitative phenotypes generated from drug frequency variables in an ADHD sample.
  
  
  METHODS
  35 SNPs were genotyped in and around DAT. We developed a quantitative phenotype at each SNP by weighting the drug frequency variables. The weights were selected to maximize the heritability at each SNP. Once a quantitative phenotype was generated at each SNP, a screening procedure was used to select and test the SNPs with the greatest power to detect an association in DAT.
  
  
  RESULTS
  No SNPs in DAT were associated with the quantitative phenotypes generated from the drug frequency variables after the multiple comparisons adjustment; however, some SNPs achieved nominal significance. A sliding window of analysis of 3 SNPs also resulted in only nominal associations.
  
  
  CONCLUSIONS
  SNPs in DAT do not appear to be associated with the phenotypes generated from drug frequency variables among individuals with ADHD.
authors.affiliation: Genetics Research Program and Department of Psychiatry and Behavioral Sciences, SUNY Upstate Medical University, Syracuse, NY 13210, and Pediatric psychopharmacology Unit, Massachusetts General Hospital, Boston, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Lasky-Su
authors.forename: Joseph
authors.initials: J
authors.lastname: Biederman
authors.forename: Alysa E
authors.initials: AE
authors.lastname: Doyle
authors.forename: Timothy
authors.initials: T
authors.lastname: Wilens
authors.forename: Michael
authors.initials: M
authors.lastname: Monuteaux
authors.forename: Jordan W
authors.initials: JW
authors.lastname: Smoller
authors.forename: Stephen
authors.initials: S
authors.lastname: Faraone
mesh_terms: D000293:Adolescent; D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics* / Q000523:psychology; D016022:Case-Control Studies; D002648:Child; D017831:Diagnosis, Dual (Psychiatry); D050483:Dopamine Plasma Membrane Transport Proteins / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D011569:Psychiatric Status Rating Scales; D019655:Quantitative Trait, Heritable; D019966:Substance-Related Disorders / Q000235:genetics* / Q000523:psychology
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins