Association study of GIT1 gene with attention-deficit hyperactivity disorder in Brazilian children and adolescents.
Attention-deficit hyperactivity disorder (ADHD) is one of the most common psychiatric disorders in children with a worldwide prevalence of 5.3%. Recently, a Korean group assessed the G-protein-coupled receptor kinase-interacting protein 1 (GIT1) gene that had previously been associated with ADHD. In their work, 27 single nucleotide polymorphisms SNPs in the GIT1 gene were tested; however, only the rs550818 SNP was associated with ADHD susceptibility. Moreover, the presence of the risk-associated allele determined reduced GIT1 expression, and Git1-deficient mice exhibit ADHD-like phenotypes. The aim of this study was to determine if this association also occurs in a sample of Brazilian children with ADHD. No effect of GIT1 genotypes on ADHD susceptibility was observed in the case-control analysis. The odds ratios (ORs) were 0.75 (P = 0.184) for the CT genotype and 1.09 (P = 0.862) for the TT genotype. In addition, the adjusted OR of the CT+TT genotypes vs. the CC genotype was also estimated (P = 0.245). There were no dimensional associations between the GIT1 genotypes and both hyperactivity and /impulsivity, and only hyperactivity Swanson, Nolan and Pelham Scale-Version IV (SNAP-IV) scores (P = 0.609 and P = 0.247, respectively). The transmission/disequilibrium test indicated that there was no over-transmission of rs550818 alleles from parents to ADHD children (z = 0.305; P = 0.761). We conclude that rs550818 is not associated with ADHD in this Brazilian sample. More studies are required before concluding that this polymorphism plays a role in ADHD susceptibility.
Genetics Department, Hospital de Clínicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
A
A
Salatino-Oliveira
J P
JP
Genro
R
R
Chazan
C
C
Zeni
M
M
Schmitz
G
G
Polanczyk
T
T
Roman
L A
LA
Rohde
M H
MH
Hutz
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics*; D000293:Adolescent; D000483:Alleles; D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology / Q000235:genetics*; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D018797:Cell Cycle Proteins / Q000235:genetics*; D002648:Child; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide
D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins; C485647:GIT1 protein, human