Linkage analysis of attention deficit hyperactivity disorder.
Results of behavioral genetic and molecular genetic studies have converged to suggest that both genes contribute to the development of ADHD. Although prior linkage studies have produced intriguing results, their results have been inconsistent, with no clear pattern of results emerging across studies. We genotyped 5,980 SNPs across the genome in 1,187 individuals from families with children diagnosed with ADHD. We then performed two nonparametric linkage analyses on ADHD families: (1) an affected sibling pair linkage analysis on 217 families with 601 siblings diagnosed with ADHD and (2) a variance components linkage analysis using the number of ADHD symptoms as the phenotype on 260 families with 1,100 phenotyped siblings. The affection status linkage analysis had a maximum LOD score of 1.85 on chromosome 8 at 54.2 cM. The maximum LOD score in the variance components linkage analysis was 0.8 on chromosome 8 at 93.4 cM. The absence of regions of significant or suggestive linkage in these data suggest that there are no genes of large effect contributing to the ADHD phenotype.
Faraone
Stephen V
SV
The Genetics Research Program and Department of Psychiatry, SUNY Upstate Medical University, Syracuse, New York 13210, USA. faraones@upstate.edu
Doyle
Alysa E
AE
Lasky-Su
Jessica
J
Sklar
Pamela B
PB
D'Angelo
Eugene
E
Gonzalez-Heydrich
Joseph
J
Kratochvil
Christopher
C
Mick
Eric
E
Klein
Kristy
K
Rezac
Amy J
AJ
Biederman
Joseph
J
D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000235:genetics*; D002648:Child; D002898:Chromosomes, Human, Pair 8; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D007407:Interviews as Topic; D008126:Lod Score; D008297:Male; D020641:Polymorphism, Single Nucleotide; D035781:Siblings